**Coupling Regional and Global Processes: Towards the Next Generation of
Space Missions**

Director's Research and Development Fund (DRDF)

\[\] Interim or \[x\] Final Report

JPL Task \# 1150

Duane Waliser, 3246, Water & Carbon Cycles, Sciences Division

Qinbin Li, 3247, Lab Studies and Modeling, Science Division

Annmarie Eldering, 3283, Tropospheric Emission Spectrometer, Science
Division

Yi Chao, 3248, Ocean-Atmos. Interaction, Science Division

Kuo-Nan Liou, Department of Atmospheric and Oceanic Sciences (AOS), UCLA

Yongkang Xue, Department of Geography, UCLA

Jinwon Kim, Department of AOS, UCLA

Alex Hall, Department of AOS, UCLA

Robert Fovell, Department of AOS, UCLA

**A. OBJECTIVES**

Develop a comprehensive Regional Earth System Model (RESM) that contains
advanced treatments of meteorology, air-quality and land-surface
processes available. The development phase will result in the
availability of a next-generation RESM that can be used to address a
number of key scientific and mission-related objectives. The RESM is
based on taking the most advanced regional atmospheric model (TRL 5) and
coupling it to a highly sophisticated land surface model (TRL 5) as well
as the state-of-the-art chemical transport/air quality model (TRL 5).
The land surface model embodies three critical processes that make it
stand apart from other schemes as well as be highly relevant to
near-term JPL mission objectives. The first is the capability to track
water variability and fluxes across the landscape in terms of detailed
treatments of runoff, soil moisture, evapo-transpiration, etc. which
relate to mission concepts such as SMAP, SWOT, and GRACE. The second is
the capability to provide fluxes of CO~2~, net primary productivity
(NPP), and the impacts from weather/ climate processes on these fluxes,
which relates to the OCO mission. The third is its capability to model
snow amount and cover in a more rigorous fashion than other land surface
schemes and this has considerable relevance to the cold lands mission
concept designed to address snow cover, snow water equivalent,
freeze/thaw conditions, etc. The chemical transport/air quality model
provides a comprehensive treatment of the emissions, physical/ chemical
transformation, and transport of air pollutants such as O~3~ and
particulates (i.e., aerosols), which relate to mission concepts such as
GEOCAPE and CACM follow-on. Its capability to model fluxes of EPA
designated pollutants such as NO~2~, SO~2~ and HCHO enables a "top-down"
constraint on their emission inventories, which is one of the core
objectives of the air quality missions being recommended by the NRC
decadal survey. The model's capability to resolve the boundary layer in
terms of ozone and aerosol variability with high spatiotemporal
resolution is indispensable for exploiting current (e.g., TES, OMI) and
future air quality satellite observations and for defining future
missions. Once completed and tested, the RESM (TRL 7) will be capable of
addressing a range of scientific questions related to the interactions
and complexities associated with the land-atmosphere hydrological cycle,
the effects of ecosystem variability on weather and climate, the impact
of land-vegetation interactions on air quality, the manner atmospheric
composition and air quality might impact weather and climate evolution
and variability, the extent and mechanisms that climate change will
impact regional air quality, water availability, and extreme weather
events, etc. Moreover, it will provide the unique means to develop and
test satellite retrieval algorithms under a wide range of highly
realistic conditions and alternative scenarios that cannot otherwise be
accounted for using tools and resources currently available. For this
regional model, interactions with the global-scale atmosphere and ocean
will be afforded either through "observed" global analyses products
*(for model validation and/or retrieval testing)* or global climate
model simulations *(for alternative scenario testing)*.

# B. APPROACH AND RESULTS 

The specific tasks include coupling the atmospheric, land surface and
air quality models into a unified, high-resolution RESM, followed by
performing a set of simulations and analyzing them in conjunction with
satellite and/or in-situ data to illustrate their synergistic benefits.
The centerpiece of the RESM is based on the Weather Research and
Forecasting Model (WRF), a "next-generation" regional atmospheric model
recently developed by the weather research and forecasting community
\[3\]. WRF features multiple options for treating atmospheric dynamics
and other physical processes, a data assimilation system, and a software
architecture allowing for computational parallelism *and system
extensibility*. We will exploit this latter feature in order to
incorporate the Community Multi-Scale Air Quality (CMAQ) \[1, 2, 4\]
model and the land-biosphere modeling system referred to as Simplified
Simple Biosphere Model (SSiB; TRL 5) \[5,6\]. The former is a
comprehensive, state-of-the-art air quality model developed and used by
the EPA that treats emissions, photochemistry, and chemical transport.
The tasks needed to couple these two models include developing the
mechanisms to pass the velocity, temperature, humidity, pressure,
precipitation and radiative fluxes within WRF to CMAQ. SSiB is a
comprehensive land-surface modeling scheme that simulates the complex
and heterogeneous interactions between land surface processes, hydrology
and the biosphere, including advanced treatments of snow processes and
CO~2~ fluxes. The specific tasks necessary to couple these models are
developing the mechanisms to pass the fluxes of heat and moisture, solar
and infrared radiation, and momentum between WRF and SSiB. The latter
will provide output information on soil moisture, surface runoff, snow
cover and amount, surface temperature, etc. Schematically this coupling
is represented by the 3 ovals in Figure 1 with solid circles outlining
them (3 to the right).

To date the WRF-SSiB coupling is nearly complete. Evaluations have been
made using simulations for June 1998. Preliminary comparisons between
the observed, model-control and new and improved model are given in
Figure 2 for both upper-level zonal wind and snow cover. In both cases,
the new WRF-SSiB model is an improvement over the previous, simpler
version with the NOAH land surface model. The WRF-CMAQ coupling has also
been completed and a 3-day simulation has been performed for 1-3 July
2005. The results are shown in Figure 3 in terms of the mean durnal
cycle of ozone and carbon monoxide over the southern California region.
Evident is the buildup of these constituents during the morning and
their reduction in the late evening. Figure 4 shows comparisons to point
in-situ data; agreement is relatively good for ozone but carbon monoxide
shows poor agreement. It should be mentioned that the scales of
variability of the latter are quite small and it may be difficult to
find agreement with a single point measurement. Further work in this
area is underway.

# C. SIGNIFICANCE OF RESULTS 

Progress to date has resulted in a new state-of-the-art regional Earth
System model that can be used for climate studies, downscaling climate
change projections, mission design objectives, etc. By completing this
work, we are in an advantageous position to build on this modeling work
and attract additional funding in the climate and mission design
context. In particular, this work has formed the basis for three
scientific contributions to the 2008 California Environmental Protection
Agency (CalEPA) / California Energy Commission (CEC) biennial science
report on the potential impact of continued global warming on a number
of California's environmental assets and economics sectors. These three
reports will also be submitted to the corresponding peer-reviewed
special journal issue to be determined. These three reports are listed
in the Publication section and noted with asterisks.

# D.      NEW TECHNOLOGY 

None.

# E. FINANCIAL STATUS 

No funding remains.

# F.      ACKNOWLEDGEMENTS 

We wish to express thanks to the Chief Scientist and Technologist Office
for their support of this work.

# G. PUBLICATIONS 

-   D. Waliser, Y. Chao, [A. Eldering]{.underline}, R. Fovell, R.
    Friedl, [A. Hall]{.underline}, J. Kim, Q. Li, K.N. Liou, J.
    McWilliams, Y. Xue. 2007. Modeling and Observing the Earth System on
    Regional Scales: A Joint UCLA-JPL Research Effort Focused on Climate
    Variability and Change In California, Fourth Annual Climate Change
    Research Conference, September 10 - 13, 2007 Sacramento Convention
    Center, Sacramento, CA.

-   Kim. J., D. Waliser, Q. Li, K. Liou, C. Cai, Y. Chao, A.
    Eldering, R. Fovell, A. Hall, X. Qu, and Y. Xue, 2007: The JIFRESSE
    Regional Earth System Model and its application to air quality in
    California. AGU Fall meeting, GC21A-0137, December 11, 2007, San
    Francisco, California, American Geophysical Union.

-   Eldering, A., A. Hall, J. Kim, R. Fovell, Y. Chao, Q. Li, K.-N.
    Liou, J. McWilliams, D. Waliser, and Y. Xu, 2008: A projection of
    climate change on the hydroclimate in California based on CCSM3 and
    JIFRESSE RESM: A joint UCLA-JPL research effort on modeling and
    observing the Earth system on regional scales. US CLIVAR
    Summit,14-16 July 2008, Irvine, California.

-   \*\*Kim, J., Y. Chao, A. Eldering, R. Fovell, A. Hall, Q. Li, K.
    Liou, J. McWilliams, D. Waliser, Y. Xue, and Sarah Kapnick, 2008: A
    projection of the cold season hydroclimate in California in mid-21st
    century under the SRES-A1B emission scenario, Fifth Annual Climate
    Change Research Conference, September 8-10, 2008, Sacramento
    Convention Center, Sacramento, CA.

-   \*\*Hughes M. Hughes, A. Hall, J. Kim, Anthropogenic Reduction of
    Santa Ana Winds, Fifth Annual Climate Change Research Conference,
    September 8-10, 2008, Sacramento Convention Center, Sacramento, CA.

-   D. Waliser, J. Kim, K. Liou, Y. Xue, A. Eldering, A. Hall, Y.
    Chao, R. Fovell, Q. Li, J. McWilliams 2008: Anthropogenic Climate
    Changes in California: Hydroclimate, Snowpack, and Santa Ana Winds,
    Fifth Annual Climate Change Research Conference, September 8-10,
    2008, Sacramento, CA.

\*\* Also a contribution to the CEC's and CEPA's Biennial 2008
California Climate Change Report (in press), and expected peer-reviewed
submissions to an associated special issue of *Climatic Change*.

# H. REFERENCES 

\[1\] Byun, D.W. and K. Schere. 2006: EPA's Third Generation Air Quality
Modeling System: Description of the Models-3 Community Multiscale Air
Quality (CMAQ) Model. J. of Mech. Review (accepted for publication) .

\[2\] Mebust, M.R., B.K. Eder, F.S. Binkowski, and S.J. Roselle, 2003,
Models-3 Community multi-scale air quality (CMAQ) model aerosol
component, 2. Model evaluation. *Journal of Geophysical Research*,
108(D6) 4184.

\[3\] Skamarock, W. C., J. B. Klemp, J. Dudhia, D. O. Gill, D. M.
Barker, W. Wang and J. G. Powers, 2005: A Description of the Advanced
Research WRF Version 2, NCAR/TN--468+STR, NCAR, Boulder, CO, June 2005

\[4\] Sokhi, R.S., Jose, R. San, Kitwiroon, N., Fragkoua, E., Perez,
J.L., Middleton, D.R., 2006, Prediction of ozone levels in London using
the MM5--CMAQ modeling system. *Environmental Modeling & Software*, 21,
566--576.

\[5\] Xue, Y., S. Sun, D. Kahan, Y. Jiao, 2001: The impact of
parameterizations in snow physics and interface processes on the
simulation of snow cover and runoff at several cold region sites. J.
Geophy. Res. 108, 8859.

\[6\] Zhan, X., Y. Xue, G. J. Collatz, 2003: An analytical approach for
estimating CO~2~ and heat fluxes over the Amazonian region. Ecological
Modeling. 162, 97-117.

# J. FIGURES 

![](media/image1.png){width="6.185416666666667in"
height="3.2597222222222224in"}

**Figure 1.** Schematic representation of the coupled regional Earth
System model configuration, including advanced modeling components for
the Atmosphere (WRF), Land Surface (SSiB), Chemical Transport and Air
Quality (CMAQ) and through a future activity the Ocean (ROMS). Ovals
indicate main processes simulated by given component and arrows indicate
forcing and feedback mechanisms between the different components. Note
that all interactions shown are realizable in the near-term but not all
will be implemented in the proposed activity (e.g., interactive ocean,
aerosol production from wind/land, indirect aerosol-cloud effects, NO2
flux from land). This DRDF activity specifically connected the
Atmosphere to the Land via SSiB and the Atmosphere to the Chemical
Transport and Air Quality via CMAQ.

![](media/image2.pct){width="3.967361111111111in" height="3.0in"}

![](media/image3.pct){width="4.016666666666667in"
height="3.0027777777777778in"}

> **Figure 2.** (top) Comparison of observed (upper) and modeled zonal
> wind at 200mb from the standard WRF model (right) and the version that
> includes the SSiB land surface component (left). (bottom) Same except
> for snow cover. Note that the "MM5" designation in the figures should
> be "WRF", and the NOAH designation is the standard/control land
> surface model.

![](media/image4.png){width="5.7in" height="3.2395833333333335in"}

**Figure 3**. The WRF-CMAQ-simulated mean diurnal cycle of O~3~ and CO
concentrations in Southern California domain for the 3-day period 1-3
July 2005.

![](media/image5.png){width="4.5in" height="3.0520833333333335in"}

**Figure 4.** Hourly concentrations of O3 and CO in Pasadena (top row)
and West LA (bottom row) in the WRF-CMAQ simulation (solid lines) and
CARB (dashed lines) during the 3-day period 1-3 July 2005.