Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A warmer world might not be a wetter one

18.10.2005


A NASA study is offering new insight into how the Earth’s water cycle might be influenced by global change.


Regions like the Persian Gulf in the Middle East, shown here by NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) instrument, may face increasingly severe water shortages as global climate changes. CREDIT: NASA GSFC


This map of sea surface temperatures was produced using MODIS data on the Terra satellite. The red pixels show warmer surface temperatures, while yellow and green are middle values, and blue represents cold water. CREDIT: NASA GSFC



In recent years, scientists have warned that the water cycle may be affected by temperature changes, as warmer temperatures can increase the moisture-holding capacity of air.

The global water cycle involves the transfer of water molecules between the Earth’s land masses, cryosphere, oceans and atmosphere. It’s a gigantic system powered by the sun, fueling a continuous exchange of moisture between the oceans, atmosphere and land.


Most climate models have shown that that a warmer climate will increase global evaporation and precipitation, but the atmospheric storage of water vapor has not yet been well studied.

Recently, researchers from NASA Goddard Space Flight Center, Greenbelt, Md., produced climate simulations of the early and late 20th century. They used sea surface temperature (SST) data and two computer models designed at Goddard Space Flight Center to determine how long water stays in the atmosphere. This is one way of measuring how the global water cycle might be influenced by changes in many variables, including temperature and precipitation.

Despite model differences, both simulations showed an increase in global evaporation and precipitation during this period. But, it is important to recognize that simulated atmospheric temperatures also increased during this period, raising the atmosphere’s "total precipitable water" - the amount of liquid water in the atmosphere if all water vapor were suddenly condensed.

"By computing a diagnostic for the water cycle rate, which accounts for total atmospheric water vapor and the average rate of precipitation, the models show the water cycling rate is reduced as the temperature warms," said Michael Bosilovich, lead author of the study, published in the May 2005 issue of the American Meteorological Society’s Journal of Climate.

When the researchers studied precipitation simulated over land and sea, they found it decreased over land as the local recycling of water vapor was reduced. Oceanic precipitation, however, had an upward trend along with increased sea surface temperatures, consistent with historical data and earlier studies.

"But, it should be noted that these contrasting land and ocean trends are not universally applicable to all regions," said Bosilovich. "For instance, the precipitation over the North American continent increases, while it decreases over the Gulf of Mexico."

The study also found that land sources of water for precipitation vary considerably within individual regions. Over time, the continental cycle of water appeared to decline, except in the central United States, where it might increase. But, further study is needed with a regional focus to accurately determine local recycling rates.

"In regard to the global scale, satellite data is an essential tool in assessing the rate and intensity of the global water cycle. It helps to identify the background state of the climate, but is limited by its short duration of record and deficiencies within historical products," said Bosilovich. "This study highlights the importance of continued high quality, well-maintained observations of atmospheric water content and precipitation rates over both the land and ocean well into the future so that we can more accurately assess changes in the water cycle."

Today, NASA’s Aqua and Terra satellites are providing such data by giving new, detailed information on processes that contribute to the water cycle. Ultimately these findings, coupled with data from future satellites, will be incorporated into regional and global computer models, improving both short-term weather forecasts and long-term climate forecasts. Such seasonal predictions carry significant economic implications and are also critical to water resource managers in determining water availability and management.

Other research programs like the NASA Energy and Water Cycle Study also use data from NASA satellites to help scientists learn more about the link between climate and the water cycle, improving their ability to predict events like floods and droughts.

Rob Gutro | EurekAlert!
Further information:
http://www.nasa.gov

More articles from Power and Electrical Engineering:

nachricht Six-legged robots faster than nature-inspired gait
17.02.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Did you know that IR heat plays a central role in the production of chocolates?
14.02.2017 | Heraeus Noblelight GmbH

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>