Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Africa, from a CATS point of view

09.03.2015

From Saharan dust storms to icy clouds to smoke on the opposite side of the continent, the first image from NASA's newest cloud- and aerosol-measuring instrument provides a profile of the atmosphere above Africa.

The Cloud-Aerosol Transport System instrument (CATS), was launched Jan. 10 aboard a SpaceX Dragon spacecraft, and was installed on the International Space Station on Jan. 22. From its berth on the station, CATS sends laser pulses toward Earth, detecting the photons that bounce off of particles in the atmosphere to measure clouds, volcanic ash, pollutants, dust and other aerosols.


Caption

This cross-section of the atmosphere over Africa shows clouds, dust and smoke from fires, as well as topography returned by the Cloud-Aerosol Transport System (CATS) instrument aboard the International Space Station.

Credit: NASA

"Everything's turned on and we're getting data, both daytime and nighttime," said Matt McGill, principal investigator of CATS from NASA's Goddard Space Flight Center in Greenbelt, Maryland. "We can see the ground, stratus clouds, cirrus clouds and over Africa we can see desert dust. The photon-counting detection approach used in CATS appears to be more sensitive than previous lidar [light detection and ranging] sensors."

The CATS image shows a profile of particles in the atmosphere over a swath of Africa, from 30 degrees North to 30 degrees South, as the space station flew over it in the early morning of Feb. 11.

Over northern Africa, particles - likely dust kicked up by Saharan windstorms - reach heights of 2.5 to 3 miles (4 to 5 kilometers), said John Yorks, science lead for CATS at Goddard. As the space station approached the equator, the instrument picked up higher atmospheric particles - thin, wispy ice clouds as high as 10 miles above the surface (16 km).

South of the cloudy tropics, aerosols appeared closer to the ground, likely smoke from biomass burning. The results from CATS can also be combined with images of Earth from instruments like the Moderate Resolution Imaging Spectroradiometer, flown on the Terra and Aqua satellites.

The CATS team is calibrating data from the two wavelengths on the primary laser operating now - 532 nanometers and 1064 nanometers. The backup laser on CATS has three wavelengths. The different wavelengths reflect differently when they hit aerosols, so comparing the returns from multiple wavelengths allows the scientists to distinguish dust from ice, smoke or other airborne particles.

"The differences between wavelengths are subtle, but the ratio of the intensity of the reflection at different wavelengths indicate aerosol type," Yorks said. The CATS team will also look at other characteristics of the laser pulse returns to help with particle identification.

Before receiving data plots like the one over Africa, the team aligned the telescope pointing. They used motors to adjust optics inside the instrument during nighttime segments until they got the strongest signal, indicating that the telescope's field of view aligned with the reflected laser photons.

"It's a difficult process, and it took us several days to get the telescope aligned," Yorks said. "But once we did, we were able to see these really small features, such as the thin cirrus clouds and the thin aerosol layers."

Data from CATS will help scientists model the structure of dust plumes and other atmospheric features, which can travel far distances and impact air quality. Climate scientists will also use the CATS data, along with data from other Earth-observing instruments, to look at trends and interactions in clouds and aerosols over time.

CATS is not only a science instrument, but a demonstration of how researchers can use the space station as a base for Earth-observing studies.

"The ISS is an interesting, low-cost platform for demonstrating new Earth Science measurements and technologies," McGill said. "For example, the ability to downlink data, continuously, in near-real time is a great advantage for testing flow of data into predictive models. However, practical limitations come with the ISS platform. For example, interruptions to operations occur due to visiting vehicle arrivals and departures. If your science demands 100 percent operational duty cycle, then ISS may not be the platform of choice."

The CATS team is moving forward with calibration and improving computer programs to identify types of aerosols, and by April hopes to be able to provide a data product to aerosol monitoring groups three hours after the data are collected, and provide products to the public within 12 hours.

CATS was designed and built by a small team at Goddard, with funds from the International Space Station Program's NASA Research Office, which also provided a spot on the station. Funding for the processing of data comes from NASA's Earth Science Division. The instrument is designed to operate for at least six months, with a goal of three years.

###

For more information on CATS, visit: http://cats.gsfc.nasa.gov/

For more information on the International Space Station, visit: http://www.nasa.gov/mission_pages/station/main/index.html

Laura Niles | EurekAlert!

More articles from Physics and Astronomy:

nachricht UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire

nachricht NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>