Scientists Studying Desert Air to Understand Weather and Climate

NASA, Naval Research Laboratory (NRL) and Scripps Institution
of Oceanography scientists have assembled in the Arabian Desert to
study tiny airborne particles called aerosols and their effect on
weather and climate. The scientists are collaborating with
researchers from the United Arab Emirates Department of Water
Resources Studies and 20 other U.S., European and South African
research laboratories to decipher the complex processes controlling
the area’s climate.

The United Arab Emirates Unified Aerosol Experiment (UAE2)
mission runs from August 5 through September 30. Scientists are
using satellites, computer models and ground stations to understand
the unique “mixing bowl” of desert dust, smoke and other aerosols
created by the complex atmospheric circulations.

“The combination of man-made emissions, smoke from the Indian
subcontinent and desert dust combine in the air to make a unique
aerosol laboratory,” said Hal Maring of NASA Headquarters,
Washington.

“We have the most intensely monitored remote-sensing aerosol
network ever assembled, including two radiation and aerosol super
sites, 10 satellite instruments, six computer models, a research
aircraft and a research vessel,” said Jeff Reid, mission scientist from
NRL in Monterey, Calif. “There are 70 scientists participating, 40 of
them working in the field, from over a dozen institutions, including the
large South African and Colorado-based National Center for
Atmospheric Research (NCAR) weather modification teams,” he
added.

Aerosols have always been an interesting puzzle piece in learning
how climate works. Lighter aerosols reflect heat and sunlight and
have cooling properties. Darker aerosols absorb heat and light,
warming the atmosphere. UAE2’s mission will measure aerosol
properties, where aerosols move, and whether they add or remove
warmth. Scientists also hope to model and explain complicated
weather patterns in the coastal regions of the Arabian Gulf and the
Gulf of Oman.

By obtaining more accurate data about aerosols and their behavior,
scientists will improve computer climate models and predictions of
climate behavior in response to changes in aerosol concentrations.
To accomplish this task, NASA will start from space, using primarily
its Terra and Aqua satellites, but other satellites as well.

These satellite data will be compared to ground-based remote
sensing measurements of mineral dust and pollutant aerosols
gathered by 15 Aerosol Robotic Network instruments over land and
water, NRL’s Mobile Atmospheric Aerosol and Radiation
Characterization Observatory (MAARCO) and NASA’s Surface-
sensing Measurements for Atmospheric Radiative Transfer.

Navy researchers will use the aircraft, MAARCO and satellite data to
evaluate the Navy’s global and regional weather and aerosol-
transport computer models. The Arabian Gulf region presents a
challenge to meteorologists trying to simulate weather with computer
models, because sea-surface and land temperatures vary to
extremes and the topography varies dramatically. There are also
strong small to medium-sized weather changes ranging from one
storm cloud to a large cluster of thunderstorms the size of
Connecticut.

Using MAARCO, scientists from the Scripps Institution of
Oceanography and Poland’s Warsaw University will study the impact
of aerosols and clouds on incoming solar radiation and the hydrologic
cycle and energy balance in this mostly rain-free area.

“This project will complement Scripps’ effort to understand climate
change in this region of the world,” said Piotr Flatau, a research
scientist at Scripps, who will be working with Krzysztof Markowicz
and others from Warsaw University during the project. “I know the
Arabian Sea from research cruises during the Indian Ocean
Experiment (INDOEX), but the UAE2 experiment brings a new set of
challenges. While INDOEX took place in a mostly monsoonal region,
the UAE is dry and hot. The temperatures are reaching 40 degrees
Celsius (104 F) there right now and we do not expect much rain,”
Flatau said.

“The UAE Office of His Highness the President, Department of Water
Resource Studies (DWRS), is providing extensive logistical support,
including access to five weather radars and 50 surface stations,” said
Lt. Col. Mangoosh, Office of the President of the United Arab
Emirates.

For more information and images on the Internet, visit: http://www.gsfc.nasa.gov/topstory/2004/0818uae2.html For more information about the UAE2 Mission, visit: http://uae2.gsfc.nasa.gov/