Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




WATER WORLD
Summer rain more likely over drier soils
by Staff Writers
Vienna, Austria (SPX) Sep 17, 2012


The new data contradicts established computer models. A conclusive explanation for this effect has yet to be found. "The air over dry soils heats up more easily. This could lead to a more intense vertical draft", Dorigo suspects. However, this cannot yet be described at a sufficient level of detail with today's computer simulations.

Summer rain is more likely over drier soil - this is the conclusion scientists have drawn from a detailed analysis of satellite data. State-of-the-art computer models predict the opposite effect; these models must now be reconsidered, says the study published in the journal "Nature".

Several international research groups were involved in the project: The Centre for Ecology and Hydrology (Wallingford, UK), the VU University Amsterdam, the Center of Meteorology CNRM in Toulouse, and the Vienna University of Technology.

Frontal rain systems, moving from the ocean across the land, can lead to rain over large areas. Summer showers, which frequently occur at the end of a hot day, are often restricted to a rather small region.

This kind of rain is a completely different phenomenon. Instead of moving across the land, the air moves from the hot ground upwards, forming clouds high up in the air, and finally leading to rain. This is called "convective precipitation".

Does Soil Moisture Lead to More Rain?
"It's tempting to assume that moist soils lead to higher evaporation, which in turn stimulates more precipitation", says Wouter Dorigo (Vienna University of Technology), one of the authors of the study. "This would imply that there is a positive feedback loop: moist soils lead to even more rain, whereas dry regions tend to remain dry."

But observations suggest otherwise: "We have analyzed data from different satellites measuring soil moisture and precipitation all over the globe, with a resolution of 50 to 100 kilometers. These data show that convective precipitation is more likely over drier soils", says Wouter Dorigo.

The new data contradicts established computer models. A conclusive explanation for this effect has yet to be found. "The air over dry soils heats up more easily. This could lead to a more intense vertical draft", Dorigo suspects. However, this cannot yet be described at a sufficient level of detail with today's computer simulations.

Microwaves from Space
Soil moisture can be measured with satellites using microwave radiation. Unlike visible light, microwaves can penetrate clouds.

Satellites can either measure the Earth's natural microwave radiation to calculate the local soil moisture (passive measurement) or the satellite sends out microwave pulses and measures how strongly the pulse is reflected by the surface (active measurement). From this data, the soil moisture can be calculated.

.


Related Links
Vienna University of Technology
Water News - Science, Technology and Politics






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





WATER WORLD
Former world leaders call on UN Security Council to recognize water as a top concern
New York NY (SPX) Sep 13, 2012
The world confronts a water crisis with critical implications for peace, political stability and economic development, experts warn in a new report being launched Sept. 11 jointly by the InterAction Council (IAC), a group of 40 prominent former government leaders and heads of state, together with the United Nations University's Institute for Water, Environment and Health, and Canada's Walter and ... read more


WATER WORLD
Norway supplies $168M for famine relief

Haunting 'Land of Hope' part shot on location in Fukushima

Japan slams brakes on $63 billion in spending

25 killed in ammunition depot blast in western Turkey: army

WATER WORLD
Appeals court suspends suit on Google book scanning

Apple gets record 2 million iPhone 5 orders

European industry develops space safety radar

Nano-velcro clasps heavy metal molecules in its grips

WATER WORLD
Summer rain more likely over drier soils

Parched soils trigger more storms

Environmental group says 'Nemo' endangered

The Gravity of Water

WATER WORLD
Surviving without ice

Little Ice Age led to migration of island hopping arctic foxes

Sailboat navigates once-frozen Arctic waterway

Glacial thinning has sharply accelerated at major South American icefields

WATER WORLD
Researchers Use "Banker Plants" to Help Battle Whitefly Pests

Screening technique uncovers five new plant activator compounds

Drought sends US producer prices surging

Turf study to monitor runoff, establish fertilizer management practices

WATER WORLD
Nicaragua ups volcano response as San Cristobal rumbles

India landslide death toll jumps to 45: minister

Eruptions weaken at Guatemala's Volcano of Fire

Santorini sees growth spurt

WATER WORLD
No peace of mind for war-weary South Sudanese

Toll rises to 40 in S. Sudan military boat sinking: army

ECOWAS defence ministers meet on Mali, G.Bissau: official

Zimbabwe's Mugabe inaugurates Chinese-built defence college

WATER WORLD
Some gains but many mysteries as Alzheimer's epidemic looms

Stress breaks loops that hold short-term memory together

How early social deprivation impairs long-term cognitive function

Mapping a genetic world beyond genes




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement