chloride bearing materials in the southern highlands of mars chlorides commonly precipitate during the evaporation of surface water or groundwater and during volcanic outgassing spectrally distinct surface deposits consistent with chloride bearing materials have been identified and mapped using data from the 2001 mars odyssey thermal emission imaging system these deposits are found throughout regions of low albedo in the southern highlands of mars geomorphologic evidence from orbiting imagery reveals these deposits to be light toned relative to their surroundings and to be polygonally fractured the deposits are small

flowgo a kinematic thermo rheological model for lava flowing in a channel we present a kinematic self adaptive numerical model to describe the down flow thermal and rheological evolution of channel contained lava as our control volume of lava advances down a channel it cools and crystallizes an increasingly thick and extensive surface crust grows and its heat budget and rheology evolve by estimating down flow heat and velocity loss our model calculates the point at which the control volume becomes stationary giving the maximum distance lava flowing in the channel can extend modeled effusion rates velocities widths surface crust parameters heat budget cooling temperature crystallinity viscosity and yield strength all compare well with field data collected during eruptions at mauna loa k lauea and etna modeled lengths of 25 27 2 5 5 7 and 0 59 0 83 km compare with measured lengths of 25 27 4 and 0 75 km for the three flows respectively over proximal flow portions we calculate cooling crystallization viscosity and yield strength of 1 10 c km 1 0 001 0 01 volume fraction km 1 103 104 pa s and 10 3 102 pa respectively at the flow front cooling crystallization viscosity and yield strength increase to 100 c km 1 0 1 volume fraction km 1 106 107 pa s and 103 104 pa respectively all of which combine to cause the lava to stop flowing our model presents a means of a analyzing lava flow thermo rheological relationships b identifying important factors in determining how far a channel fed flow can extend c assessing lava flow hazard and d reconstructing flow regimes at prehistoric unobserved or remote flows

determining soil moisture and sediment availability at white sands dune field new mexico from apparent thermal inertia data 1 determinations of soil moisture and sediment availability in arid regions are important indicators of local climate variability and the potential for future dust storm events data from the advanced spaceborne thermal emission and reflection aster radiometer were used to derive the relationships among potential soil erosion soil moisture and thermal inertia ti at the spatial scale of aeolian landforms for the white sands dune field between may 2000 and march 2008 land surface apparent thermal inertia ati data were used to derive an approximation of actual ti in order to estimate the wind threshold velocity ratio wtr the wtr is a ratio of the wind velocity thresholds at which soil erosion occurs for wet soil versus dry soil the aster derived soil moisture retrievals and the changes through time at white sands were interpreted to be driven primarily by precipitation but the presence of a perched groundwater table may also influence certain areas the sediment availability of dunes active playa surfaces and the margin of the alluvial fans to the west were determined to be consistently higher than the surrounding area the sediment availability can be primarily explained by precipitation events and the number of dry days prior to the data acquisition other factors such as vegetation and the amount of surface crusting may also influence soil mobility but these were not measured in the field this approach showed the highest modeled sediment availability values just days prior to the largest dust emission event at white sands in decades such an approach could be extended to a global monitoring technique for arid land systems that are prone to dust storms and for other regional land surface studies in the sahara

mosaicking of global planetary image datasets 2 modeling of wind streak thicknesses observed in thermal emission imaging system themis daytime and nighttime infrared data 1 large scale seamless global mosaics such as the thermal emission imaging system themis mosaics can be used to assess regional and local scale relative thermophysical properties morphology geology and other compositional investigations in this paper we use the themis global mosaics as reconnaissance tools to assess the relative thermophysical properties of materials and target a specific location to examine with a quantitative thermal model this example highlights the utility of these new data sets through an investigation of the thermophysical properties of wind streaks near the syrtis major and uranius mons regions in this study we quantitatively model depositional wind streak thicknesses near syrtis major for a thermophysically homogeneous substrate and a top layer consistent with air fall dust using this two layer thermal model we calculate that wind streaks near syrtis major are likely 30 200 m thick depending on the top layer thermal inertia given predicted dust deposition and removal rates we calculate that these wind streaks likely formed in 200 mars years and represent some of the youngest aeolian features on mars the regional wind patterns identified using the themis daytime and nighttime temperature mosaics were related to general circulation model data to constrain the season and time of day that best match the observed wind directions the themis global mosaics provide excellent context for integrating data from other instruments and provide the basis for interpreting many physical mineralogical and morphologic aspects of mars

construction dynamics of a lava channel we use a kinematic gps and laser range finder survey of a 200 m long section of the muliwai a pele lava channel mauna ulu kilauea to examine the construction processes and flow dynamics responsible for the channel levee structure the levees comprise three packages the basal package comprises an 80 150 m wide a a flow in which a 2 m deep and 11 m wide channel became centred this is capped by a second package of thin 45 cm thick sheets of pahoehoe extending no more than 50 m from the channel the upper most package comprises localised a a overflows the channel itself contains two blockages located 130 m apart and composed of levee chunks veneered with overflow lava the channel was emplaced over 50 h spanning 30 may 2 june 1974 with the flow front arriving at our section 4 4 km from the vent 8 h after the eruption began the basal a a flow thickness yields effusion rates of 35 m3 s 1 for the opening phase with the initial flow advancing across the mapped section at 10 m min short lived overflows of fluid pahoehoe then built the levee cap increasing the apparent channel depth to 4 8 m there were at least six pulses at 90 420 m3 s 1 causing overflow of limited extent lasting no more than 5 min brim full flow conditions were thus extremely short lived during a dominant period of below bank flow flow depth was 2 m with an effusion rate of 35 m3 s 1 consistent with the mean output rate obtained from the total flow bulk volume of 23 54 m3 s 1 during pulses levee chunks were plucked and floated down channel to form blockages in a final low effusion rate phase lava ponded behind the lower blockage to form a syn channel pond that fed a a overflow after the end of the eruption the roofed over pond continued to drain through the lower blockage causing the roof to founder drainage emplaced inflated flows on the channel floor below the lower blockage for a further 10 h the complex processes involved in levee channel construction of this short lived case show that care must be taken when using channel dimensions to infer flow dynamics in our case the full channel depth is not exposed instead the channel floor morphology reflects late stage pond filling and drainage rather than true channel contained flow components of the compound levee relate to different flow regimes operating at different times during the eruption and associated with different effusion rates flow dynamics and time scales for example although high effusion rate brim full flow was maintained for a small fraction of the channel lifetime it emplaced a pile of pahoehoe overflow units that account for 60 of the total levee height we show how time varying volume flux is an important parameter in controlling channel construction dynamics because the complex history of lava delivery to a channel system is recorded by the final channel morphology time varying flow dynamics can be determined from the channel morphology developing methods for quantifying detailed flux histories for effusive events from the evidence in outcrop is therefore highly valuable we here achieve this by using high resolution spatial data for a channel system at kilauea this study not only indicates those physical and dynamic characteristics that are typical for basaltic lava flows on hawaiian volcanoes but also a methodology that can be widely applied to effusive basaltic eruptions

a search for basaltic to intermediate glasses on mars assessing martian crustal mineralogy multiple datasets have demonstrated that the crust of mars is fundamentally basaltic however spectral libraries used to interrogate thermal infrared spectra of martian dark regions through spectral deconvolution have heretofore lacked mafic glasses despite the importance of amorphous phases or phases with amorphous like spectral signatures in martian mineralogy to establish the presence and importance of basaltic to intermediate glasses in martian lithologies we created five such glasses obtained their thermal infrared spectra and included the spectra in a library used to deconvolve nine regional thermal emission spectrometer spectra from mars we employed the nonnegative least squares nnls deconvolution method which yields deconvolved phase abundances and the uncertainties associated with those abundances the basaltic to intermediate glasses do not appear in the deconvolution solutions indicating they are not globally or regionally important phases because martian igneous or impact processes are capable of basaltic to intermediate glass formation the lack of such glasses in the deconvolved mineralogies suggests either the glasses did not form in detectable quantities or they or their signatures have been removed the masking or replacement of basaltic to intermediate glasses through alteration is supported by the appearance in the deconvolution solutions of amorphous phases e g silica rich glasses opal or phases with amorphous like spectral signatures e g clays zeolites that commonly form through aqueous alteration of mafic glasses the glasses may still be important to local scale thermal infrared studies given the basaltic nature of mars and the variety of local scale lithologies detected by various missions the regional mineralogies derived from the nnls deconvolution analysis divide into five statistically separable groups which provide insight into regional trends in mineralogy

what can thermal infrared remote sensing of terrestrial volcanoes tell us about processes past and present on mars over the past fifty years a diverse set of thermal infrared tir remote sensing data has been acquired from the orbits of earth and mars which both have ubiquitous volcanic landforms these data vary in spatial spectral and temporal resolution and are critical for investigating an ever expanding set of science applications including the focus of this review paper volcanic processes volcanic studies using tir data include active monitoring of flows and plumes on earth and mapping the compositional and thermophysical diversity on mars furthermore recent advances in high resolution low cost ground and laboratory tir instrumentation now help to augment the orbital data through a synergistic approach to data analysis and validation field and laboratory studies also serve as terrestrially focused analogues that provide important insights to interpret the geologic processes that have operated on other planetary surfaces including mars this review expands upon our invited talk of the same title at the 2014 geological society of america meeting to include several case studies designed to give the reader an overview of how tir data can be applied to volcanic processes on earth and mars these case studies highlight prior work by the authors presented at past meetings but which have not been published elsewhere the examples were chosen specifically to identify the tir data similarities between the two planets and include analyses of volcanic surfaces to 1 derive composition and texture using tir spectra earth and mars 2 analyze mantled flows with thermophysical data earth and mars 3 estimate lava discharge rate using tir derived temperature earth with application to mars and 4 model flow dynamics based on geomorphic measurements mars because of our focus on the tir we do not attempt to document other remote sensing wavelength regions nor even every volcanic study using tir data as tir instruments have improved over time along similar trajectories the higher spatial and spectral resolutions provide the ability to examine volcanic processes in more quantitative ways despite the fact that no tir instrument has ever been designed solely to study volcanic phenomena whether these trends continue for both planets will depend on the design of new tir technologies the data they produce and the science that results from the data

simulations of the 2004 lava flow at etna volcano using the magflow cellular automata model since the mechanical properties of lava change over time lava flows represent a challenge for physically based modeling this change is ruled by a temperature field which needs to be modeled magflow cellular automata ca model was developed for physically based simulations of lava flows in near real time we introduced an algorithm based on the monte carlo approach to solve the anisotropic problem as transition rule of ca a steady state solution of navier stokes equations was adopted in the case of isothermal laminar pressure driven bingham fluid for the cooling mechanism we consider only the radiative heat loss from the surface of the flow and the change of the temperature due to mixture of lavas between cells with different temperatures the model was applied to reproduce a real lava flow that occurred during the 2004 2005 etna eruption the simulations were computed using three different empirical relationships between viscosity and temperature

different impacts of various el nino events on the indian ocean dipole our early work wang and wang in j clim 26 1322 1338 2013 separates el nino modoki events into el nino modoki i and ii because they show different impacts on rainfall in southern china and typhoon landfall activity the warm sst anomalies originate in the equatorial central pacific and subtropical northeastern pacific for el nino modoki i and ii respectively el nino modoki i features a symmetric sst anomaly distribution about the equator with the maximum warming in the equatorial central pacific whereas el nino modoki ii shows an asymmetric distribution with the warm sst anomalies extending from the northeastern pacific to the equatorial central pacific the present paper investigates the influence of the various groups of el nino events on the indian ocean dipole iod similar to canonical el nino el nino modoki i is associated with a weakening of the walker circulation in the indo pacific region which decreases precipitation in the eastern tropical indian ocean and maritime continent and thus results in the surface easterly wind anomalies off java sumatra under the bjerknes feedback the easterly wind anomalies induce cold sst anomalies off java sumatra and thus a positive iod tends to occur in the indian ocean during canonical el nino and el nino modoki i however el nino modoki ii has an opposite impact on the walker circulation resulting in more precipitation and surface westerly wind anomalies off java sumatra thus el nino modoki ii is favorable for the onset and development of a negative iod on the frame of the bjerknes feedback

global distribution composition and abundance of olivine on the surface of mars from thermal infrared data 1 we used spectral indexing and linear deconvolution to compare thermal infrared emission spectra of fo91 fo68 fo53 fo39 fo18 and fo1 olivine samples to mars global surveyor thermal emission spectrometer tes data over low albedo regions of mars the fo91 fo68 fo53 and fo39 spectral end members were confidently identified on mars a range of compositions wider than inferred from martian meteorites small less than hundreds of square kilometers occurrences of the fo91 spectral end member are present in the rims of the argyre and hellas impact basins and may represent martian mantle materials the fo68 spectral end member is common throughout the highlands chasmata outflow channels and nili fossae region the fo53 spectral end member occurs in eastern syrtis major the nili fossae region and smooth floored craters of the highlands although less abundant than fo68 and fo53 the distribution of the fo39 spectral end member suggests that some olivine on mars is more fe rich than olivine in martian meteorites global maps of olivine show that 1 materials containing 10 20 of olivine are common in the southern highlands of mars 2 olivine is most common near the topographic dichotomy boundary and 3 olivine becomes uncommon near the poles suggesting that it may be influenced by topography and or latitude climate olivine is found in early noachian to amazonian terrains some of which may be coeval with phyllosilicate and sulfate deposits detected by omega implying that any early noachian wet period of mars climate history may have been globally inhomogeneous or insufficient to weather the olivine that remains today

interannual variability in a tropical atmosphere ocean model influence of the basic state ocean geometry and nonlinearity abstract the behavior of a tropical coupled atmosphere ocean model is analyzed for a range of different background states and ocean geometries the model is essentially that of cane and zebiak for the tropical pacific except only temporally constant background states are considered here for realistic background states and ocean geometry the model solutions feature oscillations of period of 3 5 yr by comparing the full model solution with a linearized version of the model it is shown that the basic mechanism of the oscillation is contained within linear theory a simple linear analog model is derived that describes the nature of the interannual variability in the coupled tropical atmosphere ocean system the analog model highlights the properties that produce coupled atmosphere ocean instability in the eastern ocean basin and the equatorial wave dynamics in the western ocean basin that are responsible for a delayed negative feedback into this instability growth the growth rate of the local instabil

the chemical composition of martian soil and rocks returned by the mobile alpha proton x ray spectrometer preliminary results from the x ray mode the alpha proton x ray spectrometer apxs on board the rover of the mars pathfinder mission measured the chemical composition of six soils and five rocks at the ares vallis landing site the soil analyses show similarity to those determined by the viking missions the analyzed rocks were partially covered by dust but otherwise compositionally similar to each other they are unexpectedly high in silica and potassium but low in magnesium compared to martian soils and martian meteorites the analyzed rocks are similar in composition to terrestrial andesites and close to the mean composition of earth s crust addition of a mafic component and reaction products of volcanic gases to the local rock material is necessary to explain the soil composition

volcanism on mars more than 15 years of planetary exploration of mars have given insight into the geologic processes that have shaped its surface the newly acquired viking data have shown that volcanism is one of the most important geologic processes operating on mars throughout its history in situ chemical analyses of martian soil by the viking lander spacecraft indicate mafic to ultramafic source rocks this is consistent both with available remote sensing data which indicate the presence of mafic minerals such as pyroxene and olivine and with petrologic modeling based on available geophysical data which suggest that martian lavas are probably iron rich and ultramafic these data strongly suggest that basaltic volcanism is widespread on mars and much of the photogeological data may be studied in this context photogeological analysis of the martian surface has shown two main types of volcanic morphologies the first type is central volcanoes which are volcanic landforms developed by continued and prolonged eruption from a point source vent this category includes 1 shields the classic low profile volcanic mountains of which olympus mons is the most spectacular example 2 domes steep sided constructs such as tharsis tholus that may represent lower rates of eruption than the shields or possibly more silicic lava compositions 3 highland patera radially textured low profile volcanoes that occur in the cratered terrain and are interpreted as ash shields 4 alba patera an apparently unique volcanic landform consisting of a vast volcanic center over 1500 km across with flank slopes of less than a tenth of a degree and 5 various small features such as cinder cones the second major category is volcanic plains which are units recognized by several criteria of which the presence of mare ridges and flow lobes are the most useful volcanic plains are subdivided into four main groups 1 simple flows broad smooth to rolling plains that contain numerous mare type ridges but no flow lobes interpreted as being composed of thick single cooling units 2 complex flows displaying multiple overlapping flow lobes interpreted to be indicative of thin multiple cooling units 3 undifierentiated flows plains that typically lack any morphologic identifying feature but are considered to be volcanic partly on the basis of their association with large volcanic centers and 4 questionable plains volcanic units heavily modified by other processes erosion tectonism etc so that their origins are uncertain when these categories of volcanic morphologies are combined with relative age data provided by crater statistics a volcanic history for mars can be derived as follows early heavy bombardment of mars was accompanied and followed by small scale fluvial channeling extensive flood volcanism the plateau plains and ash shield volcanism in the cratered terrain shortly after this time less extensive flood volcanism continued to resurface the planet during formation of the northern southern hemisphere dichotomy central volcanism became more prominent with the development of the alba patera center as well as the older shields and domes of the northern hemisphere early tharsis and elysium regions the development of the tharsis and elysium uplifts may have triggered the release of large scale catastrophic floods producing large channels continued uplift and lithospheric thinning concentrated volcanic activity in the tharsis region producing large shield volcanoes and extensive lava plains both central vent and plains volcanism have been active throughout martian history but the volumes of extrusion have gradually decreased with time this is consistent with a moonlike thermal history involving a lithosphere of increasing thickness with time gradually turning off the volcanism although many questions remain regarding martian volcanism the viking data have provided a remarkable detailed overview of the probable nature of the volcanic history of mars

spectral evidence for weathered basalt as an alternative to andesite in the northern lowlands of mars mineral abundances derived from the analysis of remotely sensed thermal emission data from mars have been interpreted to indicate that the surface is composed of basalt surface type 1 and andesite surface type 2 1 the global distribution of these rock types is divided roughly along the planetary dichotomy which separates ancient heavily cratered crust in the southern hemisphere basalt from younger lowland plains in the north andesite 1 but the existence of such a large volume of andesite is difficult to reconcile with our present understanding of the geological evolution of mars here we reinterpret martian surface rock lithologies using mineral abundances from previous work1 and new mineralogies derived from a spectral end member set representing minerals common in unaltered and low temperature aqueously altered basalts our results continue to indicate the dominance of unaltered basalt in the southern highlands but reveal that the northern lowlands can be interpreted as weathered basalt as an alternative to andesite the coincidence between locations of such altered basalt and a suggested northern ocean basin implies that lowland plains material may be composed of basalts weathered under submarine conditions or weathered basaltic sediments transported into this depocentre

tharsis sourced relatively dust free lavas and their possible relationship to martian meteorites abstract the launch sites for martian snc meteorites remain unknown but they must derive from young volcanic provinces we present the first geologic and spectroscopic characteristics of a suite of relatively dust free lava flows that extend from underneath the regional dust cover on the south flank of the tharsis volcanic province on mars the purpose of this work is to 1 characterize these flows geologically by using thermal emission imaging system themis data supplemented by mars orbital laser altimeter mola mars orbital camera moc and high resolution imaging science experiment hirise datasets and 2 use thermal emission spectrometer tes data in order to test the hypothesis that tharsis represents a source for the sncs these flows are morphologically similar to flood lavas in amazonis planitia with the flow surfaces being a complex mixture of surficial materials with limited exposure the spectrally derived mineral composition and geochemistry for three flows reveals basaltic compositions that have an affinity with sncs especially the basaltic shergottites however discrepancies between spectra and mineral percentages for the flows versus the shergottites together with the observation of surface deposits on the flow surfaces make any connection between these flows and the sncs tenuous although not impossible further testing of a tharsis snc relationship will require measurements at finer spatial resolutions perhaps even in situ

temperature of an active lava channel from spectral measurements kilauea volcano hawaii a narrow band spectroradiometer was used to determine the characteristic temperatures of a very active channeled lava flow for the phase 50 eruption of pu u o o on the east rift zone of kilauea volcano hawaii during the twilight of 19 february 1992 14 spectra of this activity were acquired over a 51 minute interval 18 29 to 19 20 hawaiian standard time hst from which the thermal distribution of energy of two 18 m2 areas one near the center and one near the margin of the flow may be investigated a twocomponent thermal mixing model applied to the data taken of the center of the channel gave in the most powerful instance 1 8x105 w m2 a crust temperature of 940 c a hot component temperature of 1120 c and a hot radiating area of 60 of the total area a simultaneous spectrum acquired near the channeled flow margin yielded a crust temperature of 586 c and a hot area of only 1 2 of the total area radiating at 1130 c average radiant flux densities recorded for the center of the lava channel 1 3x105 w m2 average are much greater than previous measurements of lava lakes 4 9x103 w m2 or recently emplaced lava flows maximum of 7 2x104 w m2 the energetic nature of this eruption is shown by satellite measurements made at 02 33 hst on 22 february 1992 by the advanced very high resolution radiometer in band 2 0 72 1 10 m these show the utility of using existing satellites with moderate resolution 1 km x 1 km pixels and high temporal coverage eight overpasses each day for hawaii as potential thermal alarms for rapidly assessing the hazard potential of large volcanic eruptions

the asian summer monsoon an intercomparison of cmip5 vs cmip3 simulations of the late 20th century the boreal summer asian monsoon has been evaluated in 25 coupled model intercomparison project 5 cmip5 and 22 cmip3 gcm simulations of the late twentieth century diagnostics and skill metrics have been calculated to assess the time mean climatological annual cycle interannual variability and intraseasonal variability progress has been made in modeling these aspects of the monsoon though there is no single model that best represents all of these aspects of the monsoon the cmip5 multi model mean mmm is more skillful than the cmip3 mmm for all diagnostics in terms of the skill of simulating pattern correlations with respect to observations additionally for rainfall convection the mmm outperforms the individual models for the time mean the interannual variability of the east asian monsoon and intraseasonal variability the pattern correlation of the time pentad of monsoon peak and withdrawal is better simulated than that of monsoon onset the onset of the monsoon over india is typically too late in the models the extension of the monsoon over eastern china korea and japan is underestimated while it is overestimated over the subtropical western central pacific ocean the anti correlation between anomalies of all india rainfall and nino3 4 sea surface temperature is overly strong in cmip3 and typically too weak in cmip5 for both the enso monsoon teleconnection and the east asian zonal wind rainfall teleconnection the mmm interannual rainfall anomalies are weak compared to observations though simulation of intraseasonal variability remains problematic several models show improved skill at representing the northward propagation of convection and the development of the tilted band of convection that extends from india to the equatorial west pacific the mmm also well represents the space time evolution of intraseasonal outgoing longwave radiation anomalies caution is necessary when using gpcp and cmap rainfall to validate 1 the time mean rainfall as there are systematic differences over ocean and land between these two data sets and 2 the timing of monsoon withdrawal over india where the smooth southward progression seen in india meteorological department data is better realized in cmap data compared to gpcp data

high resolution thermal inertia derived from the thermal emission imaging system themis thermal model and applications 1 thermal inertia values at 100 m per pixel are determined using nighttime temperature data from the thermal emission imaging system themis on the mars odyssey spacecraft producing the highest resolution thermal inertia data set to date themis thermal inertia values have an overall accuracy of 20 a precision of 10 15 and are consistent with both thermal emission spectrometer orbital and miniature thermal emission spectrometer surface thermal inertia values this data set enables the improved quantification of fine scale surface details observed in high resolution visible images in the tharsis region surface textures and crater rims observed in visible images have no corresponding variation in the themis thermal inertia images indicating that the dust mantle is pervasive at themis scales and is a minimum of a few centimeters and up to 1 2 m thick the thermal inertia of bed form material indicates particle diameters expected for aeolian sediments and these materials are likely currently saltating variations in the thermal inertia within interior layered deposits in hebes chasma can be distinguished and the thermal inertia is too low to be consistent with bedrock or a lava flow thus a secondary emplacement of volcanic material or a volcanic ash deposit is a more likely method of formation higher resolution themis thermal inertia enables the identification of exposed bedrock on the martian surface in nili patera and ares vallis bedrock material corresponds to distinct compositional and morphologic surfaces indicating that a specific unit is exposed and is likely currently being kept free of unconsolidated material by aeolian processes

simulating the thermorheological evolution of channel contained lava flowgo and its implementation in excel flowgo is a one dimensional model that tracks the thermorheological evolution of lava flowing down a channel the model does not spread the lava but instead follows a control volume as it descends a line of steepest descent centred on the channel axis the model basis is the jeffreys equation for newtonian flow modified for a bingham fluid and a series of heat loss equations adjustable relationships are used to calculate cooling crystallization and down channel increases in viscosity and yield strength as well as the resultant decrease in velocity here we provide a guide that allows flowgo to be set up in excel in doing so we show how the model can be executed using a slope profile derived from google tm earth model simplicity and ease of source term input from google tm earth means that this exercise allows i easy access to the model ii quick global application and iii use in a teaching role output is tested using measurements made for the 2010 eruption of piton de la fournaise la reunion island the model is also set up for rapid syneruptive hazard assessment at piton de la fournaise as we show using the example of the response to the june 2014 eruption

surface textures and dynamics of the 2005 lava dome at shiveluch volcano kamchatka shiveluch is one of the largest and most active andesitic volcanoes of the kuril kamchatka arc it commonly alternates between vulcanian explosive eruptions and periods of dome growth and subsequent dome collapse driven block and ash flows the volcano was in an extended period of heightened activity for most of the period 2004 2010 we examined this activity in detail using thermal infrared tir remote sensing as part of the urgent request protocol urp program of the advanced spaceborne thermal emission and reflection radiometer aster instrument and confirmed the results with ground based photography and airborne tir camera data high spatial resolution tir images were collected during both daytime and nighttime satellite overpasses prior to and following the large explosive event eruption of 27 february 2005 and the dome growth that followed during a field campaign in august 2005 a helicopter overflight designed to acquire visible and tir data of the active dome was performed this was a nadir looking low altitude overflight and the first ever of shiveluch volcano involving non russian scientists the image data revealed an active crease structure in the center of the dome with a distinctly different crescent shaped high temperature 380 c zone roughly perpendicular to the crease in order to provide a time context and estimate extrusion rates the airborne data were compared to the spaceborne aster data and long distance ground based photography of the dome acquired by our russian colleagues the presence of a crease structure and the complex thermal pattern on the surface were both unexpected discoveries that reveal the way in which exogenous dome growth was occurring at the time this highly active period at shiveluch provides a unique example to better understand silicic lava dome growth using tir data the results also demonstrate a straightforward approach for fusing ground air and spaceborne image data which could be applied to other active domes around the world

influence of the state of the indian ocean dipole on the following year s el nino el nino southern oscillation enso consists of irregular episodes of warm el nino and cold la nina conditions in the tropical pacific ocean 1 with significant global socio economic and environmental impacts 1 nevertheless forecasting enso at lead times longer than a few months remains a challenge 2 3 like the pacific ocean the indian ocean also shows interannual climate fluctuations which are known as the indian ocean dipole 4 5 positive phases of the indian ocean dipole tend to co occur with el nino and negative phases with la nina 6 9 here we show using a simple forecast model that in addition to this link a negative phase of the indian ocean dipole anomaly is an efficient predictor of el nino 14 months before its peak and similarly a positive phase in the indian ocean dipole often precedes la nina observations and model analyses suggest that the indian ocean dipole modulates the strength of the walker circulation in autumn the quick demise of the indian ocean dipole anomaly in november december then induces a sudden collapse of anomalous zonal winds over the pacific ocean which leads to the development of el nino la nina our study suggests that improvements in the observing system in the indian ocean region and better simulations of its interannual climate variability will benefit enso forecasts

estimation of volcanic eruption conditions for a large flank event on elysium mons mars mars orbiter camera image 5 23 m pixel and topographic data from the mars orbiter laser altimeter data are used to analyze a channel on the upper northern flank of the elysium mons volcano mars we show that this channel is best explained as the product of the thermal erosion of the preexisting surface by a high speed turbulent lava flow fed from a fissure eruption we deduce the volume eruption rate 3400 13 000 m3 s dense rock equivalent the total volume of erupted lava 29 39 km dense rock equivalent and the duration of the activity 40 130 days perhaps significantly the erupted lava volume is essentially identical given the uncertainties in the analysis to the volume of the observed caldera 31 km3 which has implications for volume limited eruptions on mars and potentially for the unusual steep upper slopes of the volcano the eruption that produced the channel appears to have been typical for elysium mons and implies that the other lava channels on the upper flank of the volcano may also have taken 1 4 months to have formed

a triggering mechanism for the indian ocean dipoles independent of enso abstractalthough the indian ocean dipole iod and enso are significantly correlated there are indeed some iods independent of enso in this research the characteristics of independent iod are investigated and a new triggering mechanism is proposed based on case study and statistical analysis results show that the independent iods peak in an earlier season and have a weaker intensity compared with the iods associated with enso the wind anomaly associated with the independent iod is very unique and shows a monsoonlike pattern in addition to the equatorial easterly wind anomaly eewa common to all iods the evolution of the eewa associated with the independent iod is well captured by the second eof mode of the equatorial zonal wind interannual variability suggesting that the independent iod is an important climate mode inherent to the tropical indian ocean the eewa associated with the independent iod is tightly linked to indian summer monsoon activities in spring and the convection anomalies associ

observations of the madden julian oscillation during indian ocean dipole events 1 the characteristics of madden julian oscillation mjo development and propagation during indian ocean dipole iod events are presented in this study we find that mjo activity over the indian ocean and maritime continent is enhanced during negative iod and subdued during positive iod mjo events occurring during positive iod have weaker convection and less organized wind anomalies than those occurring during neutral or negative iod these differences are starkest over the eastern indian ocean where the iod has the greatest effect on low level humidity based on these observations and current mjo theories we posit that the iod primarily influences the mjo through its modulation of local low level moisture

characteristics of subsurface ocean response to enso assessed from simulations with the ncep climate forecast system abstractthe subsurface ocean temperature response to el nino southern oscillation enso is examined based on 31 yr 1981 2011 simulations with the national centers for environmental prediction ncep climate forecast system cfs coupled model the model sea surface temperature sst in the tropical pacific is relaxed to observations to ensure realistic enso variability in the simulations in the tropical pacific the subsurface temperature response to the enso sst is closely related to the variability of thermocline the subsurface response is stronger and deeper in the tropical indian ocean than in the tropical atlantic the analysis at three selected locations reveals that the peak response of the subsurface temperature to enso lags the nino 3 4 sst by 3 6 and 6 months respectively in the southern tropical indian ocean the northern tropical atlantic and the north pacific where ssts are also known to be strongly influenced by enso the enso forced temperature anomalies gradually penetrate to the

thermal inertia mapping of mars from 60 s to 60 n twenty micrometer brightness temperatures are used to derive the thermal inertia for 81 of the martian surface between latitudes 60 these data were acquired by the two viking infrared thermal mappers in 1977 and 1978 following the two global dust storms of 1977 the spatial resolution used is 2 in latitude by 2 in longitude and the total range in derived inertia is 1 to 15 10 3 cal cm 2 sec 12 k 1 the distribution of thermal inertia is strongly bimodal with all values of thermal inertia less than 4 10 3 cal cm 2 sec 12 k 1 being associated with three disjoint bright regions mostly in the northern hemisphere sufficient dust is raised in global storms to provide fine material adequate to produce these low inertia areas but the specific deposition mechanism has not been defined at the low resolution used no complete exposures of clean rock were found there is some tendency for darker material to be associated with higher thermal inertia although the trend is far from one to one the distribution of high and low inertia areas is sufficiently nonrandom to produce a variation in whole disk brightness temperature with central meridian longitude this variation and the change in surface kinetic temperature associated with dust storms are factors in establishing the whole disk brightness temperature at radio and infrared wavelengths and will be important for those who use mars as a calibration source

recovery of spectral emissivity from thermal infrared multispectral scanner imagery acquired over a mountainous terrain a case study from mount etna sicily the estimation of ground radiance and emissivity from thermal infrared multispectral scanner tims data is strongly dependent on the atmospheric correction applied to these data since such corrections are a function of the atmospheric path between the sensor and ground correction techniques that do not consider the topographic variations within a scene can introduce appreciable error in the estimation of the atmosphere effects in this paper we describe the development and application of a variable elevation atmospheric correction procedure our objective was to incorporate changes in target altitude into a general atmosphere correction strategy this procedure was tested on a tims data set acquired over mt etna italy in july 1986 the methodology adopted in this study is based on the use of the lowtran radiative transfer code and a digital elevation model dem registered to the image data the image data are divided into a series of layers based on elevation and a separate atmosphere correction is applied to each layer maps of emissivity estimates derived with the variable elevation approach were compared with geologic maps of the etna flow fields prior to the variable elevation correction the emissivity spectra of long lava flows appeared to vary with elevation following the variable elevation correction many of these spectral artifacts were removed from the emissivity maps in addition the variable elevation correction increased our ability to discriminate individual lava flows

alkaline volcanic rocks from the columbia hills gusev crater mars 1 irvine backstay and wishstone are the type specimens for three classes of fine grained or fragmental relatively unaltered rocks with distinctive thermal emission spectra found as float on the flanks of the columbia hills chemical analyses indicate that these rocks are mildly alkaline basalt trachybasalt and tephrite respectively their mineralogy consists of na and k rich feldspar s low and high ca pyroxenes ferroan olivine fe ti and possibly cr oxides phosphate and possibly glass the texture of wishstone is consistent with a pyroclastic origin whereas irvine and backstay are lavas or possibly dike rocks chemical compositions of these rocks plot on or near liquid lines of descent for most elements calculated for adirondack class rocks olivine rich basalts from the gusev plains at various pressures from 0 1 to 1 0 gpa we infer that wishstone backstay and irvine class magmas may have formed by fractionation of primitive oxidized basaltic magma similar to adirondack class rocks the compositions of all these rocks reveal that the gusev magmatic province is alkaline distinct from the subalkaline volcanic rocks thought to dominate most of the planet s surface the fact that differentiated volcanic rocks were not encountered on the plains prior to ascending husband hill may suggest a local magma source for volcanism beneath gusev crater

beyond the spring barrier predicting an el nino or la nina event before the preceding spring has proved to be difficult taking into account coupled ocean atmosphere modes in the indian ocean region that have a two year periodicity may provide the basis for longer forecasting lead times

relative dating of hawaiian lava flows using multispectral thermal infrared images a new tool for geologic mapping of young volcanic terranes the weathering of hawaiian basalts in arid and semiarid environments is accompanied by change in their thermal infrared emittance spectra the spectral differences can be measured and mapped with multispectral imaging systems the differences appear to be related to the degree of development preservation and alteration of glassy crusts the oxidation of iron and the accretion of silica rich surface veneers because the measurements are quantitative and in image format they are useful for estimating relative ages in geologic mapping of lava flows in hawaii this technique is most diagnostic for distinguishing among sparsely vegetated flows less than 1 5 ka in age

regional dust deposits on mars physical properties age and history major dust storms on mars play an important role in the deposition and removal of fine dust material thermal radar and visual remote sensing observations provide important constraints on the martian regolith which have been used to determine the location and physical properties of regional dust deposits these deposits are located in three northern equatorial regions tharsis 20 s to 50 n 60 to 190 w arabia 5 s to 30 n 300 to 360 w and elysium 10 to 30 n 210 to 225 w they are covered by fine 2 40 m bright albedo 0 27 particles with fewer exposed rocks and coarse deposits than found elsewhere dust is currently deposited uniformly throughout the equatorial region at a rate of 40 m global storm over geologic time the rate of accumulation may vary from 0 to 250 m yr due to changes in atmospheric conditions produced by orbital variations dust deposited during global storms is subsequently removed only from dark regions resulting in a net accumulation in the low inertia bright regions the thickness of these current dust deposits is 0 1 2 m the thermal inertia places a lower limit of 0 1 m on the thickness of these deposits while the sparse but ubiquitous presence of exposed rocks and the degree of visible mantling indicate that the thickness is less than 5 m dual polarization radar observations of a very rough texture in tharsis are consistent with this model with a 2 m thick dust layer burying most of the surface rocks but permitting radar sampling of the rough subsurface based on their thickness and rate of accumulation the age of these deposits is 105 106 years suggesting a cyclic process of deposition and removal one possible cause may be cyclic variations in the magnitude and location of maximum wind velocities related to variations in mars orbit at present perihelion and maximum wind velocities occur in the south whereas regional dust deposits occur in the north suggesting net transport from south to north orbital parameters oscillate with periods ranging from 5 104 to 106 years the agreement between these periods and the dust deposit age suggests a possible link at different stages in orbit evolution maximum wind velocities will occur in the north with subsequent erosion and redistribution of the accumulated fines based on this model much of the uppermost martian surface is very young and is being continually reworked

extremes of the indian summer monsoon rainfall enso and equatorial indian ocean oscillation it is well known that anomalies of the indian summer monsoon rainfall ismr are linked to el nino and southern oscillation enso we show that large anomalies of the ismr are also linked to the equatorial indian ocean oscillation equinoo between states with enhancement suppression of atmospheric convection over the western part of the equatorial indian ocean with suppression enhancement over the eastern part and associated changes in the anomaly of the zonal wind along the equator equinoo is the atmospheric component of the coupled indian ocean dipole mode there is a strong relation between the large anomalies of ismr and a composite index which is a linear combination of the indices for enso and equinoo with all seasons with large deficits excess characterized by small large values of the index however the variation of ismr within one standard deviation is more complex and does not appear to be related to the composite index

evidence for extensive olivine rich basalt bedrock outcrops in ganges and eos chasmas mars 1 several localized outcrops of olivine enriched bedrock have been previously identified in the ganges and eos chasma area on the eastern end of valles marineris with the thermal emission imaging system multispectral images these outcrops form a layer in the walls of ganges chasma and appear to be the remnants of a once continuous unit which was mapped over 100 km in this study we further characterize the composition forsterite content of 0 68 olivine abundance 10 to 15 thermal inertia 600 jk 1 m 2 s 1 2 consistent with in place rocky material vertical dimension 60 to 220 m extent 1100 km laterally volume 9 9 104 km3 dip 0 013 ne and continuity of this layer utilizing thermal emission spectrometer hyperspectral thermal emission imaging system multispectral and mars orbiter laser altimeter elevation data morphologic data from high resolution imagery display a relatively unmantled rough and pitted surface associated with the olivine enriched material consistent with thermal inertia data four possibilities for the origin of the olivine enriched unit are 1 volcanism associated with tectonic rifting of the valles marineris system 2 a volcaniclastic flow deposit 3 an intrusive mafic sill or 4 a discrete episode in martian history during which flood lavas were erupted onto the surface the most likely origin is an eruptive event consisting of compositionally uniform flood lavas originating from a primitive mantle source region possibly associated with the initiation of tharsis volcanism this unit is one of the largest continuous compositional units found on mars and is strikingly similar to other olivine enriched deposits identified in previous studies where compositional morphologic and thermophysical similarities are observed these similarities may indicate that there was a period in early martian history where compositionally uniform and extensive olivine enriched flood basalts were erupted on the martian surface

spatial variations in lava flow field thermal structure and effusion rate derived from very high spatial resolution hyperspectral mivis data 1 high spatial resolution hyperspectral measurements of volcanic thermal anomalies allow for an unconstrained solution of a two component thermal model this can be used for identification of lava flow emplacement style and the calculation of lava flow heat and volume flux the multispectral infrared and visible imaging spectrometer mivis is an airborne sensor equipped with 72 bands in the short infrared range and 10 bands in the thermal infrared region of the spectrum we used mivis acquired for mount etna italy during the july august 2001 eruption to solve the dual band equations in an unconstrained fashion using three bands of unsaturated data our results suggest a complex thermal structure for etnean lava flows this is characterized by a downflow transition from a lightly crusted active channel to a more heavily crusted distal section both surrounded by zones of stagnant cooling flow where exposed molten material is absent and maximum temperatures are thus lower the total flow field effusion rate obtained for 29 july 2001 0700 local time of 8 16 m3 s is in excellent agreement with that obtained from ground based measurements and advanced very high resolution radiometer data flow by flow effusion rates obtained from the mivis data vary depending on whether the vent is linked to the central conduit or the dyke that was injected from greater depth as well as vent elevation with lower elevation vents experiencing higher effusion rates

using infrared satellite data to drive a thermo rheological stochastic lava flow emplacement model a method for near real time volcanic hazard assessment 1 we combine two flow simulation models to provide a computationally efficient means of predicting the final dimensions of active lava flows by using a stochastic approach to predict all the downhill paths that a lava flow could possibly follow and a thermo rheological model to terminate these paths once the predicted cooling limited length for the flow has been attained this approach allows for rapid assessment of the area likely to be inundated by lava the 1991 1993 eruption of mount etna is used as a case study lava effusion rate exerts a strong control on the maximum length a lava flow can attain and we demonstrate how the model can be driven by time varying effusion rates obtained from infrared satellite data as such data are obtained in near real time this approach allows flow simulations to be updated in a timely manner in response to changing eruption conditions

ducks low cost thermal monitoring units for near vent deployment abstract during 1999 we designed and tested a thermal monitoring system to provide a cheap robust modular real time system capable of surviving the hostile conditions encountered proximal to active volcanic vents in november 2000 the first system was deployed at pu u o o kilauea hawai i to target persistently active vents aside from some minor problems such as sensor damage due to tampering this system remained operational until january 2004 the success of the prototype system led us to use the blueprint for a second installation at stromboli aeolian islands italy this was deployed dug into a bomb proof bunker during may 2002 and survived the april 2003 paroxysmal eruption despite being located just 250 m from the vent in both cases careful waterproofing of connectors and selection of suitable protection has prevented water damage and corrosion in the harsh atmosphere encountered at the crater rim the pu u o o system cost us 10 000 and comprises four modules sensors transmission and power hub repeater station and reception site the sensor component consists of three thermal infrared thermometers housed in pelican cases fitted with germanium arsenide selenium windows two 1 field of view fov sensors allow specific vents to be targeted and a 60 fov sensor provides a crater floor overview a hard wire connection links to a pelican case housed microprocessor modem and power module from here data are transmitted via a repeater site to a dedicated pc at the hawaiian volcano observatory here data are displayed with a delay of 3 s between acquisition and display the modular design allows for great flexibility at stromboli 1 and 15 fov sensor modules can be switched depending changes in activity style and crater geometry in addition a direct line of site to the stromboli reception center negates the repeater site requirement reducing the cost to us 5500 for a single sensor system we have also constructed self contained units with internal data loggers for us 1500 unit these have been tested at kilauea stromboli etna masaya santiaguito fuego pacaya poas soufriere hills villarrica and erta ale these instruments have proved capable of detecting thermal signals associated with 1 gas emission 2 gas jetting events 3 crater floor collapse 4 lava effusion 5 lava flow in tubes 6 lava lake activity 7 lava dome activity and 8 crater lake skin temperature

forecasting lava flow paths by a stochastic approach 1 a stochastic model named downflow is presented to forecast possible lava flow paths with the aim of hazard assessment and mitigation the model relies on the fact that lava flow emplacement is in many cases controlled by topography the potential inundation area of the flow is determined by considering a number of steepest paths over stochastic perturbations of the original topography since the code requires very short computational time and few input data the model proved to be a very useful tool to obtain real time predictions during the initial phase of an eruption the necessary topographic information can be obtained by photogrammetry radar altimetry or laser scanning techniques downflow has been successfully applied to a number of flows including the september 2004 lava flow where updated topographies were available

near real time forecasting of lava flow hazards during the 12 13 january 2011 etna eruption we are grateful to eumetsat for seviri data to nasa for modis data and tonoaafor avhrr data the authors thank one anonymous reviewer and v acocella for their helpful and constructive comments this study was performed with the financial support from the v3 lava project ingv dpc 2007 2009 contract

magma crystallization and viscosity a study of molten basalts from the piton de la fournaise volcano la reunion island abstract the viscosity of three molten basalts produced by fusion of lavas issued from different eruptions of the piton de la fournaise la reunion island has been investigated above the liquidus and at high degrees of supercooling for all basalts crystallization took place rapidly above the glass transition range which made static measurements problematic because of time dependent non newtonian rheology by contrast reproducible results were obtained in dynamic measurements made at a constant heating rate of 5 k mn partial crystallization resulted in strong viscosity increases which were primarily due to the presence of solid inclusions comparisons with phase equilibria experiments performed for the same samples at higher temperatures show that crystallization takes place differently below the liquidus and at strong degrees of supercooling as recently described for simpler systems these differences in nucleation and growth are controlled by the relative mobilities of the cations diffusing within the melt to attach themselves to crystal melt interfaces a consequence is that the composition evolution of the residual melt differs in equilibrium and irreversible crystallization in turn this contrast induces opposite viscosity variations for the residual melt

origin of the medusae fossae formation mars insights from a synoptic approach 1 the geologic origin of the medusae fossae formation mff has remained a mystery despite three decades of research to better constrain its formation an in depth analysis of observations made in the literature was combined with a new survey of over 700 mars orbiter camera narrow angle images of the mff to identify morphologic characteristics and material properties that define this formation as a whole while previous work has identified clear agreement on some characteristics our analysis identifies yardangs collapse features and layering as pervasive features of the mff whereas collapse features and layering may implicate several different physical and chemical processes yardangs provide vital information on material properties that inform about mechanical properties of the mff lithology aspect ratios of megayardangs range from 3 1 to 50 1 and slope analyses reveal heights of up to 200 m with cliffs that are almost vertical other yardangs show lower aspect ratios and topographic profiles these characteristics coupled to the presence of serrated margins suggest that mff lithology must be of weakly to heavily indurated material that lends itself to jointing the characteristics and properties of the mff are inconsistent with those of terrestrial pyroclastic fall deposits or loess but are in common with large terrestrial ignimbrites a hypothesis that explains all key observations with a single mechanism yardang fields developed in regionally extensive ignimbrite sheets in the central andes display morphologic characteristics that correlate with degree of induration of the host lithology and suggest an origin by pyroclastic flow for the mff

covariations between the indian ocean dipole and enso a modeling study the coevolution of the indian ocean dipole iod and el nino southern oscillation enso is examined using both observational data and coupled global climate model simulations the covariability of iod and enso is analyzed by applying the extended empirical orthogonal function eeof method to the surface and subsurface ocean temperatures in the tropical indian ocean and western pacific the first eeof mode shows the evolution of iod that lags enso whereas the second mode exhibits the transition from a dipole mode to a basin wide mode in the tropical indian ocean that leads enso the lead lag relationships between iod and enso are consistent with two way interactions between them a comparison between two 500 year model simulations with and without enso shows that enso can enhance the variability of iod at interannual time scale the influence of enso on the iod intensity is larger for the eastern pole than for the western pole and further is stronger in the negative iod phase than in the positive phase the influence of iod on enso is demonstrated by the improvement of enso prediction using sea surface temperature sst in the tropical indian ocean as an enso precursor the improvement of the enso forecast skill is found at both a short lead time 0 month and long leads 10 15 months the sst in the western pole has more predictive value than in the eastern pole the eastward propagation of surface and subsurface temperature signals from the western indian ocean that precedes the development of heat content anomaly in the tropical western pacific is the key for extending the lead time for enso prediction our results are consistent with previously reported findings but highlight the spatial temporal evolution of the enso iod system it is also illustrated that iod would have been more helpful in predicting the 1997 98 el nino than the 2015 16 el nino

morphometric properties of martian volcanoes 1 mars orbiter laser altimeter mola data have been used to construct digital elevation models dem of the martian volcanoes in order to determine height flank slope caldera depth and volumes summit elevations range from 21 1 km to 0 5 km and relief varies from 1 0 km to almost 22 km average flank slopes are in the range of 1 to 10 consistent with basaltic shield volcanism the very low slopes of highland patera are also consistent with pyroclastic volcanism minimum volumes range from 1012 to 1015 m3 estimates of the time required to build these volcanoes on the basis of long term terrestrial eruption rates range from hundreds of thousands to tens of millions of years

effects of martian conditions on numerically modeled cooling limited channelized lava flows 1 we used the flowgo thermorheological model to examine the effects of martian gravitational and environmental conditions on the cooling limited behavior of lava flowing in a channel the largest effect is due to the lower gravity on mars as compared to earth which causes lava to flow more slowly the lower velocity means that heat loss per distance down a mars channel is greater even though the lower velocity also produces a higher percentage cover of insulating crust gravity alone causes the mars flow to be 65 km shorter than an earth flow with an equivalent volumetric flow rate the cooler ambient mars atmosphere causes a slight increase in heat loss by forced convection this slows the flow a bit more resulting in a very slight increase in heat loss per distance by all mechanisms and decreases the modeled flow length by 1 km a difference well below our model uncertainty replacing terrestrial values of atmospheric density viscosity thermal conductivity heat capacity and cubic expansivity makes convection less efficient and increases flow length by 15 km nevertheless at the same volumetric flow rate lava flows 50 km less far under martian conditions than under terrestrial conditions our specific model flow has a volumetric flow rate of 5000 m3 s 1 and traveled 190 km down a channel on a constant 7 slope this volumetric flow rate is slightly less than the maximum rates during the 1783 1785 laki eruption and is 5 10 times greater than those of typical mauna loa eruptions

apparent thermal inertia and the surface heterogeneity of mars abstract thermal inertia derivation techniques generally assume that surface properties are uniform at horizontal scales below the footprint of the observing instrument and to depths of several decimeters consequently surfaces with horizontal or vertical heterogeneity may yield apparent thermal inertia which varies with time of day and season to investigate these temporal variations we processed three mars years of mars global surveyor thermal emission spectrometer observations and produced global nightside and dayside seasonal maps of apparent thermal inertia these maps show broad regions with diurnal and seasonal differences up to 200 j m 2 k 1 s 1 2 at mid latitudes 60 s to 60 n and 600 j m 2 k 1 s 1 2 or greater in the polar regions we compared the seasonal mapping results with modeled apparent thermal inertia and created new maps of surface heterogeneity at 5 resolution delineating regions that have thermal characteristics consistent with horizontal mixtures or layers of two materials the thermal behavior of most regions on mars appears to be dominated by layering with upper layers of higher thermal inertia e g duricrusts or desert pavements over fines prevailing in mid latitudes and upper layers of lower thermal inertia e g dust covered rock soils with an ice table at shallow depths prevailing in polar regions less common are regions dominated by horizontal mixtures such as those containing differing proportions of rocks sand dust and duricrust or surfaces with divergent local slopes other regions show thermal behavior that is more complex and not well represented by two component surface models these results have important implications for mars surface geology climate modeling landing site selection and other endeavors that employ thermal inertia as a tool for characterizing surface properties

effects of surface roughness and graybody emissivity on martian thermal infrared spectra slopes are present in martian apparent surface emissivity observations collected by the thermal emission spectrometer tes and the thermal emission imaging system themis these slopes are attributed to misrepresenting the surface temperature either through incorrect assumptions about the maximum emissivity of surface materials or the presumption of a uniform surface temperature within the field of view these incorrect assumptions leave distinct characteristics in the resulting apparent emissivity data that can be used to gain a better understanding of the surface properties surfaces with steep slopes typically have a variable surface temperatures within the field of view that cause distinct and highly variable slopes in apparent emissivity spectra based on the observing conditions these properties are documented on the southwestern flank of apollinaris patera and can be reasonably approximated by modeled data this spectral behavior is associated with extremely rough martian surfaces and includes surfaces south of arsia mons and near warrego valles that also appear to have high slopes in high resolution images surfaces with low maximum values of emissivity have apparent emissivity spectra with more consistent spectral slopes that do not vary greatly based on observing conditions this spectral surface type is documented in terra serenum and is consistent with associated high resolution images that do not indicate the presence of a surface significantly rougher that the surrounding terrain

retrieval of volcanic ash particle size mass and optical depth from a ground based thermal infrared camera abstract volcanoes can emit fine sized ash particles 1 10 m radii into the atmosphere and if they reach the upper troposphere or lower stratosphere these particles can have deleterious effects on the atmosphere and climate if they remain within the lowest few kilometers of the atmosphere the particles can lead to health effects in humans and animals and also affect vegetation it is therefore of some interest to be able to measure the particle size distribution mass and other optical properties of fine ash once suspended in the atmosphere a new imaging camera working in the infrared region between 7 14 m has been developed to detect and quantify volcanic ash the camera uses passive infrared radiation measured in up to five spectral channels to discriminate ash from other atmospheric absorbers e g water molecules and a microphysical ash model is used to invert the measurements into three retrievable quantities the particle size distribution the infrared optical depth and the total mass of fine particles in this study we describe the salient characteristics of the thermal infrared imaging camera and present the first retrievals from field studies at an erupting volcano an automated ash alarm algorithm has been devised and tested and a quantitative ash retrieval scheme developed to infer particle sizes infrared optical depths and mass in a developing ash column the results suggest that the camera is a useful quantitative tool for monitoring volcanic particulates in the size range 1 10 m and because it can operate during the night it may be a very useful complement to other instruments e g ultra violet spectrometers that only operate during daylight

lava discharge during etna s january 2011 fire fountain tracked using msg seviri etna s january 2011 eruption provided an excellent opportunity to test the ability of meteosat second generation satellite s spinning enhanced visible and infrared imager seviri sensor to track a short lived effusive event the presence of lava fountaining the rapid expansion of lava flows and the complexity of the resulting flow field make such events difficult to track from the ground during the etna s january 2011 eruption we were able to use thermal data collected by seviri every 15 min to generate a time series of the syn eruptive heat flux lava discharge waxed over a 1 h period to reach a peak that was first masked from the satellite view by a cold tephra plume and then was of sufficient intensity to saturate the 3 9 m channel both problems made it impossible to estimate time averaged lava discharge rates using the syn eruptive heat flux curve therefore through integration of data obtained by ground based doppler radar and thermal cameras as well as ancillary satellite data from moderate resolution imaging spectrometer and advanced very high resolution radiometer we developed a method that allowed us to identify the point at which effusion stagnated to allow definition of a lava cooling curve this allowed retrieval of a lava volume of 1 2 106 m3 which if emitted for 5 h was erupted at a mean output rate of 70 m3 s 1 the lava volume estimated using the cooling curve method is found to be similar to the values inferred from field measurements

volcanic geology of tyrrhena patera mars tyrrhena patera is a large low relief volcano located in the southern cratered highlands of mars on a proposed ring fracture of the hellas basin the volcano is composed of four or possibly five principal units the oldest and most areally extensive of which are suggested to be ash on the basis of their morphology and erosional characteristics lava flows are observed in a flank flow unit extending from the central caldera to the southwest and apparently cap the summit region models derived from the study of terrestrial pyroclastic flows have been applied to the deposits at tyrrhena patera and indicate that the distribution and lengths of the observed deposits are consistent with an origin by the emplacement of gravity driven ash flows generated by hydromagmatic or magmatic explosive eruptions the hydromagmatic case requires considerable quantities of water 7 5 1016 kg however at volumetric water flow rates determined by other investigators 105 m3 s and calculated from the regional slopes in the hesperia planum region 106 m3 s the amounts necessary could be supplied relatively rapidly in geologic time tyrrhena patera represents the earliest central vent volcanism identified on mars and may reflect a transition from the flood style eruptions which dominated early martian history a hydromagmatic origin for tyrrhena patera is in agreement with suggested climatic changes on mars and may explain the absence of this style of volcanism in later eras alternatively a magmatic origin for tyrrhena patera implies an evolution in the types of magmas produced on mars from hesperian to amazonian time during which the prominent shields in the tharsis region formed

thermal infrared 2 5 13 5 μm spectroscopic remote sensing of igneous rock types on particulate planetary surfaces fundamental molecular vibration bands are significantly diminished by scattering thus such bands in spectra of fine particulate regoliths i e dominated by 5 m particles or regoliths displaying a similar scale of porosity are difficult to use for mineralogical or rock type identification consequently other spectral features have been sought that may be more useful in spectroscopic remote sensing of composition we find that mineralogical information is retained in overtones and combination tones of the fundamental molecular vibrations in the 3 0 to 7 0 m region but that relatively few minerals have a sufficiently distinctive band structure to be unambiguously identified with currently available techniques more significantly identification of general rock type as defined by the scfm chemical index scfm sio2 sio2 cao feo mgo is possible using spectral features associated with the principal christiansen frequency and with a region of relative transparency between the si o stretching and bending bands however environmental factors may affect the appearance and wavelengths of these features finally prominent absorption bands may result from the presence of relatively small amounts of water hydroxyl or carbonate because absorption bands exhibited by these materials in the 2 7 to 4 0 m region where silicate spectra are otherwise featureless increase strongly in spectral contrast with decreasing particle size such materials are thus detectable in very small amounts in a particulate regolith composed predominantly of silicate minerals

thermal infrared spectral character of hawaiian basaltic glasses multispectral thermal infrared remote sensing of hawaiian basalts younger than a few hundred years old can be used to discriminate basalt lava flows that are difficult to map with visible and near infrared images laboratory thermal infrared reflectance spectra of the exposed surfaces of mauna loa and kilauea basalts show systematic changes with age fresh glass collected from active lava flows shows a broad reflectance feature between 8 and 12 m indicative of a strong degree of disorder after a few weeks of exposure to the environment the spectra of the top surfaces of samples begin to exhibit spectral features suggestive of ordering into silicate chainlike and sheetlike units with progressive aging features of apparent sheetlike structures become the preferred mode as soon as 3 years after emplacement a silica rich coating can begin to develop on the surfaces adding another spectral feature to the laboratory reflectance measurements the thermal infrared multispectral scanner tims with six channels between 8 and 12 m has been used to take advantage of these spectral differences in basalts to map flows in hawaii remote sensing instruments with increased spectral resolution in the thermal infrared would aid in further discrimination of basalts with more subtle differences in age quenching and weathering histories

lava effusion rate definition and measurement a review measurement of effusion rate is a primary objective for studies that model lava flow and magma system dynamics as well as for monitoring efforts during on going eruptions however its exact definition remains a source of confusion and problems occur when comparing volume flux values that are averaged over different time periods or spatial scales or measured using different approaches thus our aims are to 1 define effusion rate terminology and 2 assess the various measurement methods and their results we first distinguish between instantaneous effusion rate and time averaged discharge rate eruption rate is next defined as the total volume of lava emplaced since the beginning of the eruption divided by the time since the eruption began the ultimate extension of this is mean output rate this being the final volume of erupted lava divided by total eruption duration whether these values are total values i e the flux feeding all flow units across the entire flow field or local i e the flux feeding a single active unit within a flow field across which many units are active also needs to be specified no approach is without its problems and all can have large error up to 50 however good agreement between diverse approaches shows that reliable estimates can be made if each approach is applied carefully and takes into account the caveats we detail here there are three important factors to consider and state when measuring giving or using an effusion rate first the time period over which the value was averaged second whether the measurement applies to the entire active flow field or a single lava flow within that field and third the measurement technique and its accompanying assumptions

explosive lava water interactions ii self organization processes among volcanic rootless eruption sites in the 1783 1784 laki lava flow iceland we have applied quantitative geospatial analyses to rootless eruption sites in the hnuta and hrossatungur groups of the 1783 1784 laki lava flow to establish how patterns of spatial distribution can be used to obtain information about rootless cone emplacement processes and paleo environments this study utilizes sample size dependent nearest neighbor nn statistics and voronoi tessellations to quantify the spatial distribution of rootless eruption sites and validate the use of statistical nn analysis as a remote sensing tool our results show that rootless eruption sites cluster in environments with abundant lava and water resources but competition for limited groundwater in these clusters can cause rootless eruption sites to develop repelled distributions this pattern of self organization can be interpreted within the context of resource availability and depletion topography tends to concentrate lava fuel and water coolant within topographic lows thereby promoting explosive lava water interactions in these regions given an excess supply of lava within broad sheet lobes rootless eruption sites withdraw groundwater from their surroundings until there is insufficient water to maintain analogs to explosive molten fuel coolant interactions rootless eruption sites may be modeled as a network of water extraction wells that draw down the water table in their vicinity rootless eruptions at locations with insufficient groundwater may either fail to initiate or terminate before explosive activity has ceased at nearby locations with a greater supply of water thus imparting a repelled distribution to observed rootless eruption sites

climate science tropical atlantic warm events sea surface temperatures in the eastern equatorial atlantic ocean are subject to year to year variations reanalysis data and model simulations suggest that advection of warm water from north of the equator can drive some of the warm events

mosaicking of global planetary image datasets 1 techniques and data processing for thermal emission imaging system themis multi spectral data 1 the mosaicking of global planetary data sets allows for the examination of local regional and global scale processes on all planetary bodies processing techniques that allow us and other users to crate mosaics of tens of thousands of images are documented along with the associated errors introduced by each image processing algorithm these techniques e g non uniformity correction running contrast stretches line and row correlated noise removal and random noise removal were originally developed for the 2001 mars odyssey thermal emission imaging system themis infrared multispectral imager data but can be adapted and applied to other data sets by the alteration of input parameters the techniques for mosaicking planetary image data sets e g image registration blending and normalization are also presented along with the generation of qualitative and quantitative products these techniques are then applied to generate themis daytime and nighttime infrared viking context imager ctx and mars orbiter camera moc visible mosaics using a variety of input and output types at a variety of scales by creating mosaics of the same area using different data sets such as those that illustrate compositional diversity thermophysical properties or small scale morphology it is possible to view the surface of the planet and geologic problems through many different perspectives in addition to the techniques used to create large scale seamless mosaics we also present the themis daytime and nighttime relative temperature global mosaics which are the highest resolution 100m pixel global scale data sets available for mars to date

influence of indian ocean dipole on boreal summer intraseasonal oscillations in a coupled general circulation model 1 the role of indian ocean dipole iod on poleward propagation of boreal summer intraseasonal oscillations bsiso is examined using long simulation of a coupled ocean atmosphere general circulation model the model sintex f1 simulates the salient features of bsiso realistically it is found that coherent incoherent poleward propagation of precipitation anomalies from 5 s to 25 n are observed during negative positive iod years the probable mechanisms behind such an anomaly in poleward propagation of bsiso in contrasting iod years are identified we find that the mean structure of meridional specific humidity distribution undergoes cardinal changes in contrasting iod years which in turn influences the meridional propagation of bsiso enhanced decreased air sea interaction in negative positive iod years also supports coherent incoherent poleward propagation of bsiso anomalies this study has important implications considering the critical role of bsiso in modulating the seasonal mean summer monsoon rainfall

volcanology 2020 how will thermal remote sensing of volcanic surface activity evolve over the next decade abstract volcanological remote sensing spans numerous techniques wavelength regions data collection strategies targets and applications attempting to foresee and predict the growth vectors in this broad and rapidly developing field is therefore exceedingly difficult however we attempted to make such predictions at both the american geophysical union agu meeting session entitled volcanology 2010 how will the science and practice of volcanology change in the coming decade held in december 2000 and the follow up session 10 years later looking backward and forward volcanology in 2010 and 2020 in this summary paper we assess how well we did with our predictions for specific facets of volcano remote sensing in 2000 the advances made over the most recent decade and attempt a new look ahead to the next decade in completing this review we only consider the subset of the field focused on thermal infrared remote sensing of surface activity using ground based and space based technology and the subsequent research results this review keeps to the original scope of both agu presentations and therefore does not address the entire field of volcanological remote sensing which uses technologies in other wavelength regions e g ultraviolet radar etc or the study of volcanic processes other than the those associated with surface mostly effusive activity therefore we do not consider remote sensing of ash gas plumes for example in 2000 we had looked forward to a golden age in volcanological remote sensing with a variety of new orbital missions both planned and recently launched in addition exciting field based sensors such as hand held thermal cameras were also becoming available and being quickly adopted by volcanologists for both monitoring and research applications all of our predictions in 2000 came true but at a pace far quicker than we predicted relative to the 2000 2010 timeframe the coming decade will see far fewer new orbital instruments with direct applications to volcanology however ground based technologies and applications will continue to proliferate and unforeseen technology promises many exciting possibilities that will advance volcano thermal monitoring and science far beyond what we can currently envision

rootless cones on mars a consequence of lava ground ice interaction fields of small cratered cones on mars are interpreted to have formed by rootless eruptions due to explosive interaction of lava with ground ice contained within the regolith beneath the flow melting and vaporization of the ice and subsequent explosive expansion of the vapour act to excavate the lava and construct a rootless cone around the explosion site similar features are found in iceland where flowing lava encountered water saturated substrates the martian cones have basal diameters of c 30 1000 m and are located predominantly in the northern volcanic plains high resolution mars orbiter camera images offer significant improvements over viking data for interpretation of cone origins a new model of the dynamics of cone formation indicates that very modest amounts of water ice are required to initiate and sustain the explosive interactions that produced the observed features this is consistent with the likely low availability of water ice in the martian regolith the scarcity of impact craters on many of the host lava flows indicates very young ages suggesting that ground ice was present as recently as less than 10 l00 ma and may persist today rootless cones therefore act as a spatial and temporal probe of the distribution of ground ice on mars which is of key significance in understanding the evolution of the martian climate the location of water in liquid or solid form is of great importance to future robotic and human exploration strategies and to the search for extraterrestrial life

evolution of indian ocean dipole and its forcing mechanisms in the absence of enso the evolution of indian ocean dipole iod and its forcing mechanisms are examined based on the analysis of coupled model simulations that allow or suppress the el nino southern oscillation enso mode of variability the model can reproduce the most salient observed features of iod even without enso including the relationships between the eastern and western poles at both the surface and subsurface as well as their seasonality this suggests that enso is not fundamental for the existence of iod it is demonstrated that cold warm sea surface temperature sst anomalies in the eastern indian ocean associated with iod can be initiated by springtime indonesian rainfall deficit surplus through local surface wind response the growth of the sst anomalies depends on the initial local subsurface condition both the air sea interaction and surface subsurface interaction contribute to the development of iod the evolution of iod can be represented by two leading extended empirical orthogonal function eeof modes of tropical surface subsurface indian ocean temperatures one stationary and the other non stationary the onset growth and termination of iod as well as the transition to an opposite phase can be interpreted as alternations between the non propagating mode eeof1 and the eastward propagating kelvin wave eeof2 the evolution of iod is also accompanied by a westward propagating rossby wave which is captured in the eeof1 of the subtropical surface subsurface indian ocean temperatures therefore both bjerknes feedback and a delayed oscillator operate during the evolution of iod in the absence of enso also

global spectral classification of martian low albedo regions with mars global surveyor thermal emission spectrometer mgs tes data 1 martian low albedo surfaces defined here as surfaces with mars global surveyor thermal emission spectrometer mgs tes albedo values 0 15 were reexamined for regional variations in spectral response low albedo regions exhibit spatially coherent variations in spectral character which in this work are grouped into 11 representative spectral shapes the use of these spectral shapes in modeling global surface emissivity results in refined distributions of previously determined global spectral unit types surface types 1 and 2 pure type 2 surfaces are less extensive than previously thought and are mostly confined to the northern lowlands regional scale spectral variations are present within areas previously mapped as surface type 1 or as a mixture of the two surface types suggesting variations in mineral abundance among basaltic units for example syrtis major which was the surface type 1 type locality is spectrally distinct from terrains that were also previously mapped as type 1 a spectral difference also exists between southern and northern acidalia planitia which may be due in part to a small amount of dust cover in southern acidalia groups of these spectral shapes can be averaged to produce spectra that are similar to surface types 1 and 2 indicating that the originally derived surface types are representative of the average of all low albedo regions

a chronology of the 1991 to 1993 mount etna eruption using advanced very high resolution radiometer data implications for real time thermal volcano monitoring between december 1991 and march 1993 a continuous effusive eruption at mount etna built a 7 6 km2 lava flow field flows extended to within 1 km of the town of zafferana before a successful artificial diversion was carried out higher up the volcano during this eruption the spaceborne advanced very high resolution radiometer avhrr acquired 308 images on which the activity could be detected since these data can be freely and directly available such coverage potentially allows regular real time monitoring ground observations and a flow map that we produced using a spot image and electronic distance measurement allowed us to develop and test data extraction techniques avhrr radiance maps were consistent with known locations of surface activity these documented the transition from channel to tube fed phases the changing threat to zafferana and flow diversion quantitative analysis of the avhrr data enabled estimation of active lava area thermal flux effusion rates and total flow field volume our estimates for eruption rate and total flow field volume 5 6 to 7 6 m3 s and 220 106 to 300 106 m3 respectively are in agreement with published ground based estimates of 5 8 m3 s and 235 106 m3 these correlations demonstrate the high degree of confidence that can now be placed in interpretations of avhrr time series for eruptions where ground based data are scanty

constraining tephra dispersion and deposition from three subplinian explosions in 2011 at shinmoedake volcano kyushu japan constraining physical parameters of tephra dispersion and deposition from explosive volcanic eruptions is a significant challenge because of both the complexity of the relationship between tephra distribution and distance from the vent and the difficulties associated with direct and comprehensive real time observations three andesitic subplinian explosions in january 2011 at shinmoedake volcano japan are used as a case study to validate selected empirical and theoretical models using observations and field data tephra volumes are estimated using relationships between dispersal area and tephra thickness or mass area a new cubic b spline interpolation method is also examined magma discharge rate is estimated using theoretical plume models incorporating the effect of wind results are consistent with observed plume heights 6 4 7 3 km above the vent and eruption durations estimated tephra volumes were 15 34 106 m3 for explosions on the afternoon of 26 january and morning of 27 january and 5 0 7 6 106 m3 for the afternoon of 27 january magma discharge rates were in the range 1 2 106 kg s for all three explosions clast dispersal models estimated plume height at 7 1 1 km above the vent for each explosion the three subplinian explosions occurred with approximately 12 h reposes and had similar mass discharge rates and plume heights but decreasing erupted magma volumes and durations

the olympus mons aureole formation by gravitational spreading new observations of the aureole deposits of olympus mons are in agreement with previous suggestions that the aureole lobes could have been formed by movement under gravity away from the observed scarps the characteristic corrugated morphology of the aureole is probably secondary formed by erosion along structural inhomogeneities geometries of the corrugations and translational faults in the aureole deposits favor a mechanism of emplacement that involves material with substantial shear strength rather than viscous flow estimates of the aspect ratios of terrestrial landslides nappes and ash flows suggest that the aureole deposits are more similar in overall shape to slide emplaced bodies than to pyroclastic flows although martian physical conditions permit the formation of ash flows there is no positive evidence for their existence a gravitational spreading mechanism is proposed that involves imbricate thrusting in distal regions analogous with terrestrial thrust sheets corrugations in the aureole developed by erosion along imbricate or listric faults basal shear stresses on the decoupling surface may have been of the order of 106 pa 10 bars the nature of the decoupling surfaces in the proximal regions is uncertain but is likely to have been the topographic surface in distal parts the aureole deposits were probably emplaced as a series of sheets by spreading under gravity from an ancestral olympus mons which extended farther to the northwest than does the present volcano as a result of the accumulation of lavas under the then prevailing stress conditions recent lava eruptions from the volcano have been concentrated in northeast and southwest sectors indicating a changed stress regime since aureole emplacement