# Presentation: 536535

## Remote Sensing from the 

-    Soon-to-be-Launched Aqua
-                Spacecraft
- Claire L. Parkinson
- Aqua Project Scientist
- NASA Goddard Space Flight Center
- Presentation at the Department of Geography, Boston University, Boston, Massachusetts
- February 15, 2002

## Aqua Mission Basics

- Aqua is one of the major satellite missions of the international Earth Observing System (EOS) program, centered at NASA.
- The Aqua spacecraft will carry six distinct instruments to measure numerous aspects of the Earth’s atmosphere, oceans, ice, land, and biosphere.
- The Aqua name highlights the information the mission will obtain about the Earth’s water cycle.
- Aqua will be launched on board a Delta 7920-10L rocket from Vandenberg Air Force Base in California.
- The Aqua launch is currently scheduled for April 18, 2002.
- Terra, the first EOS spacecraft, was launched in December 1999.

## Different Depictions of the Water Cycle

- (schematics by Hailey King and GSFC)

## Instruments on Aqua

- Atmospheric Infrared Sounder (AIRS)
- Advanced Microwave Sounding Unit (AMSU)
- Humidity Sounder for Brazil (HSB)
- Moderate-Resolution                                         Imaging Spectro-                                                     radiometer (MODIS)
- Clouds and the Earth’s                                      Radiant Energy System                                      (CERES; two                                                      instruments)
- Advanced Microwave                                             Scanning Radiometer                                                for EOS (AMSR-E)

## The Aqua Science Instrumentsp.1, the Sounding Suite

- HSB

- A1

- AIRS

- ASMU

- (photos by D. Stroud)

- A2

- /           \

## The Aqua Science Instrumentsp.2, the Non-sounders

- Two CERES

- MODIS

- AMSR-E

- (photos by D. Stroud)

## Instrument Background

- The first CERES was launched on the Tropical Rainfall Measuring Mission (TRMM) in November 1997. The second and third CERES are on Terra. The next two are on Aqua.
- The first MODIS is on Terra; the second is on Aqua. The Aqua MODIS incorporates several improvements.
- The first AIRS is on Aqua. Its companion instruments, the AMSU and HSB, are similar to instruments on NOAA satellites.
- The first AMSR-E is on Aqua. It follows on the heritage of earlier passive-microwave instruments.

- CERES

- MODIS

- AIRS

- AMSR-E

## Aqua as of August 2001 at TRW, Redondo Beach, California

- Space-viewing side

- Earth-viewing side

## Aqua on its Way into the Thermal Vacuum Chamber

- (1)

- (2)

- (4)

- (3)

## The Aqua Orbit

- (animation by Jesse Allen)

## Aqua’s Orbit

- Altitude of 705 km.
- Near-polar, sun-synchronous, orbiting the Earth every 98.8 minutes, crossing the equator going north at 1:30 p.m. and going south at 1:30 a.m.

- (schematic by Jesse Allen)

## The Aqua Science Teams

- AIRS/AMSU/HSB Science Team, led by Moustafa Chahine, NASA Jet Propulsion Laboratory.
- AMSR-E U.S. Science Team, led by Roy Spencer, University of Alabama at Huntsville.
- AMSR-E Japanese Science Team, led by Akira Shibata, Japanese Meteorological Agency.
- CERES Science Team, led by Bruce Wielicki, NASA Langley Research Center.
- MODIS Science Team, led by Vincent Salomonson, NASA Goddard Space Flight Center.

## Major Objectives

- Enhanced understanding of the global water cycle.
- Enhanced understanding of many components of the Earth’s climate system and their interactions.
- Lengthening of the satellite-based record of many climate variables.
- Improved weather forecasting.
- Enhanced understanding of the diurnal cycle of variables measured by CERES and MODIS.

## Measurement Ranges of the Aqua Instruments

- ________________________________________
- uv|  visible |      infrared       |      microwave
- __| ______|_____________ _|_________________
-     | -- MODIS -- |
-     | ---- AIRS ---- |
-    | ---------- CERES ------ |
-                                                |-| HSB
-                                                        | --- AMSR-E --- |
-                                                        |----| |---| AMSU
-                                                         A1   A2

## CERES

- Measurements of clouds and radiation fluxes.
- Two scanning radiometers,                          both capable of operating in                            either of two scanning modes                          (fixed azimuth plane or                            rotating azimuth plane).
- Three channels in each                     radiometer
- Total radiance (0.3 to over 100                                                m)
- Shortwave radiance (0.3-5 m)
- Radiance in the 8-12 m atmospheric window)
- Spatial resolutions of 20 km at nadir.

## The Earth’s Radiation Budget

- (courtesy of the CERES Science Team)

## Key CERES Data Products

- Fluxes of outgoing radiation at the top of the atmosphere.
- Shortwave radiation (solar radiation reflected from the Earth/atmosphere system).
- Total radiation (reflected and emitted).
- Longwave radiation (emitted from the Earth/atmosphere system).
- Radiation in the 8-12 μm atmospheric window.
- Fluxes of shortwave and longwave radiation at the Earth’s surface.
- Fluxes of shortwave and longwave radiation at multiple levels in the atmosphere.
- Cloud properties (cloud fraction, height, optical depth, particle size, and ice/water phase).
- Aerosol optical depth.

## Sample Images from the Terra CERES

- Monthly average longwave flux, July 2000

- Night-time emitted thermal flux, March 3, 2000

## Animation of the Aqua Orbit, Revealing the CERES Swath with Sample CERES Data

- Outgoing longwave radiation, March 21, 2001, from the Terra CERES.

- (computer animation by Jesse Allen)

## Longwave and Shortwave Radiation as Determined from Data of the Terra CERES, March 2000 – May 2001

- Longwave (on left): Radiation emitted to space from the Earth system.
- Shortwave (on right): Sunlight reflected back to space.

## New Science Results from the TRMM and Terra CERES

- The tropical radiative energy budget is much more dynamic and variable than previously thought.
- Changes in the longwave and shortwave fluxes in the 1990s, versus earlier, are consistent with decreasing cloudiness.
- The radiation variations are consistent                            with a strengthening of the Hadley and                     Walker atmospheric circulation patterns                    in the 1990s.
- Evidence has been found counter to                         the Iris hypothesis that thin cirrus                        clouds in the tropics exert a large                    negative feedback in the climate                      system.

## Major CERES Validation Efforts

- The Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS) field experiment ran from July 10 to August 2, 2001.
- The long-term CERES Ocean Validation Experiment (COVE) is on-going at the Chesapeake lighthouse.
- Surface-based, aircraft, and balloon data from long-term validation sites in the Atmospheric Radiation Measure-ment (ARM) Baseline Surface Radiation Network are being used in the CERES ARM Validation Experiment (CAVE).
- COVE and CAVE are both expected to continue while Aqua is operating.

## MODIS

- Measurements of biological and physical processes within the Earth/atmosphere system. (Surface data are generally obscured in the presence of clouds.)
- Cross-track scanning radiometer.
- 36 spectral bands, with wavelengths ranging from 0.4 to 14.5 m.
- Spatial resolutions of 250 m – 1 km.
- Temporal resolutions of 1-2 days.

## Key MODIS Data Products

- Oceans
- Primary productivity, photosynthetically active radiation, coccolith concentration, chlorophyll fluorescence, pigment concentration, phycoerythrin concentration, suspended solids and organic matter concentrations, attenuation coefficient, sea surface temperature, sea ice cover, sea ice albedo.
- Atmosphere
- Cloud microphysical properties, cloud top properties, cloud mask, aerosol optical depth, aerosol size distribution, total ozone, total precipitable water, temperature and water vapor profiles.
- Land
- Net primary productivity, land cover type and change, leaf area index, fraction of photosynthetically active radiation, gridded vegetation indices, fires, burn scars, land surface temperature and emissivity, snow cover, snow albedo, atmospherically corrected surface reflectance.

## Animation of the Aqua Orbit, Revealing the MODIS Swath with Sample MODIS Data

- (computer animation by Jesse Allen)

- Mosaic of visible imagery from the Terra MODIS, May 25–Aug. 29, 2001.

## Sample Images from the Terra MODIS, p.1

- The Nile River and surroundings, February 28, 2000

- Dust over northwest Africa and vicinity, February 29, 2000

- Sea ice at the North Pole and vicinity

- Western hemisphere MODIS mosaic

## Sample Images from the Terra MODIS, p.2

- Sea Surface Temperature, May 2001 Daytime Average

- Enhanced Vegetation Index, September 30 – October 15, 2000

## Growth and Decay of Vegetation Across North America as Determined from Data of the Terra MODIS,Enhanced Vegetation Index, July 2000 – June 2001

- Growth and Decay of Vegetation Across North America as Determined from Data of the Terra MODIS,Enhanced Vegetation Index, July 2000 – June 2001

## MODIS Validation Activities

- Field experiments, including the Southern African Regional Science Initiative (SAFARI 2000), involving 17 nations.
- 24 core land-vegetation sites.
- An instrumented Marine Optical Buoy (MOBY) off the coast of Hawaii.
- A MODIS Airborne Simulator.
- Comparisons with other satellite data.

## Plans for the Aqua MODIS Data 

- Generate and analyze most of the same products as for the Terra MODIS.
- Add a new Surface Evaporation Index.
- Generate improved SSTs, benefiting from a change made to the Aqua MODIS in October 2000, reducing the saturation temperature for two of the data bands from about 400 K to about 340 K.
- Examine the diurnal cycle from the combined Terra and Aqua data.

## AIRS/AMSU/HSB

- High-spectral-resolution sounding suite measuring temperature and humidity profiles plus a wide variety of other variables.
- The most advanced sounding system ever deployed in space.
- 2382 visible and infrared channels on AIRS, plus 19 microwave channels on AMSU and HSB.
- Horizontal resolutions of 13.5 km at nadir for AIRS and HSB, 40.5 km at nadir for AMSU.
- Vertical resolutions of 1-2 km.

- HSB

- AMSU A2

- AMSU A1

- AIRS

## Key AIRS/AMSU/HSB Data Products

- Temperature profiles through the atmosphere.
- Water vapor profiles through the atmosphere.
- Total precipitable water, cloud liquid-water content, precipitation indication, cloud-ice indication.
- Heights of the tropopause and stratopause.
- Cloud-top pressure and temperature, fractional cloud cover, cloud spectral properties, and cloud type.
- Ozone profile through the atmosphere.
- Total column atmospheric ozone, methane, carbon monoxide, and carbon dioxide.
- Sea and land surface skin temperature.
- Infrared and microwave surface emissivity.
- Longwave and shortwave radiative fluxes at the top of the atmosphere and at the surface.

## Central AIRS/AMSU/HSB Goals

- Atmospheric temperature profiles to an accuracy of 1 K for every 1 km layer in the troposphere and every 4 km layer in the stratosphere.
- Humidity profiles to an accuracy of 10% in 2-km layers in the troposphere.
- Improved weather forecasts through the incorporation of AIRS/AMSU/HSB data.

- Failed forecast for Washington, D.C., January 24, 2000, when a major snowstorm struck. (Map courtesy of Brett McDonald.)

## AIRS Measurements

## AIRS/AMSU/HSB Science Preparations

- The final pre-launch Product Generation Software package has been delivered to the data center doing the data processing, archival, and distribution.
- AIRS/AMSU/HSB data flow, display, retrieval, and analysis are being tested using a “golden day” concept with December 15, 2000 simulated data.
- Validation support teams are being integrated into the validation efforts.
- The AIRS Team is working with                                        weather prediction agencies in                                     the U.S., Canada, and Europe                                       to facilitate the incorporation of                        AIRS/AMSU/HSB data into                                   weather forecasts.

## AIRS/AMSU/HSB Precursor Data

-     The TIROS Operational Vertical Sounder (TOVS) is a low-resolution precursor of AIRS/AMSU/HSB. (TIROS = Television Infrared Observation Satellite.)

## AMSR-E

- Measurements of a variety of physical processes within the Earth/atmosphere system.
- Conically scanning passive-microwave radiometer.
- Twelve channels, two each (with vertical and horizontal polarizations) at frequencies of 6.9, 10.7, 18.7, 23.8, 36.5, and 89 GHz.
- Spatial resolutions ranging from 5 km for the 89 GHz channels to 56 km for the 6.9 GHz channels.

## Key AMSR-E Data Products

- Rainfall
- Water vapor (total atmospheric column)
- Cloud water (total atmospheric column)
- Sea surface temperature
- Sea surface wind speed
- Sea ice concentration
- Sea ice temperature
- Snow depth on sea ice
- Snow-water equivalent on land
- Surface soil moisture

## AMSR-E/MODIS Complementarity 

- Several variables will be measured by both AMSR-E and MODIS.
- MODIS data will allow greater spatial detail (higher resolution).
- AMSR-E surface data will be obtainable under a wider variety of conditions.
- Under darkness as well as daylight.
- Under cloudy as well as cloud-free conditions.

- (Passive-microwave data have the advantage, for surface observations, of being obtainable under all lighting conditions and most weather conditions.)

## Advantages of AMSR-E over Currently Operating Satellite Passive-Microwave Instruments

- Improved spatial resolution (although still coarse resolution compared to visible sensors).
- Additional products.
- Soil moisture.
- Sea ice temperatures.
- Sea surface temperatures (SSTs) globally (the TRMM Microwave Imager can obtain SSTs, but the TRMM orbit restricts these to latitudes equatorward of 40°).

## Upcoming AMSR-E Science

- The AMSR-E team will extend the data records from previous passive-microwave instruments, plus add soil moisture and surface temperature records.
- Sea ice provides an example of the records to be extended, in this case from the Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR) and the DMSP Special Sensor Microwave Imager (SSMI).

- March 1998 sea ice concentrations

- Nov. 1978 – Dec. 1999 sea ice extent deviations

## AMSR-E Validation Plans

- Various validation efforts are planned, involving aircraft, ships, data buoys, radiosondes, field campaigns, and intercomparisons with other satellite data.
- Validation support teams are being integrated into the AMSR-E team and program.
- An AMSR-E simulator, the Airborne Earth Science Microwave Imaging Radiometer                         (AESMIR), is under development.

- Navy P-3 used in Meltpond2000, a pre-launch validation exercise over sea ice in the Canadian Arctic

- The AESMIR

## Simulated Data Collection by the Aqua Instruments

- (animation by Jesse Allen)

## The EOS Afternoon Satellite Constellation

- (rendering by Jesse Allen)

## Aqua Products Available at http://aqua.nasa.gov, p.1

- AMSR-E brochure

- AIRS/AMSU/HSB brochure

## Aqua Products Available at http://aqua.nasa.gov, p.2

- Aqua lithograph

- Water Cycle Fact Sheet

- Weather Forecasting Fact Sheet

## Upcoming Aqua Products, soon-to-be available at http://aqua.nasa.gov

- CERES is one of six Earth-observing instruments to be flown on board NASA’s Aqua satellite ...
-  Purpose:....
-  Size: ...
-  Data channels: ...
-  Spatial resolution of the data: ...
-  Primary data products: ...
-  Provider: ...
-  Website: ...

- Aqua brochure

- Aqua Science Writers’ Guide

- Aqua trading cards

## Aqua Webcasts

- Produced by the Goddard Special Project Initiatives Office.
- Broadcast live at http://aqua.nasa.gov (and later archived there).
- Dec. 19, 2001,                                                                     from TRW.
- Feb. 5 and 8,                                                                      2002, from                                                                       Hawaii.
- April 2002, from                                                                      the launch site.

- Dec. 19, 2001 webcast

## Aqua’s Delta II Rocket, Ready for Launch

- (rendering by Reto Stockli)

## Simulated Deployment Sequence for Aqua

## Aqua Summary

- Aqua is a major satellite mission of the Earth Observing System (EOS) program.
- Key goals:
- Improved understanding of the water cycle.
- Improved understanding of additional elements of the climate system.
- Improved weather forecasting.
- Six distinct Earth-observing instruments
- Measuring in different wavelength regions, with different resolutions and different characteristics.
- Launch: Delta rocket, from Vandenberg Air Force Base, currently scheduled for April 18, 2002.
- Orbit: 705 km altitude, crossing the equator going north at 1:30 p.m. and going south at 1:30 a.m., orbiting the Earth once every 98.8 minutes.

## Backups

## The Mauna Loa Record of Atmospheric Carbon Dioxide Concentrations

- (courtesy of Scripps Institute of Oceanography and NOAA)

- 310 ppm

- 330 ppm

- 350 ppm

- 370 ppm

## A Sampling of Global Changes

- ARCTIC SEA ICE

-  (photo by C. Tucker)

- ANTARCTIC SEA ICE

- DEFORESTATION

## Sample Images from the Terra CERES, p.2

- Net cloud radiative forcing for July 2000

## The Delta Rocket and its Aqua Payload

- (rendering by Reto Stockli)