Featured Research

from universities, journals, and other organizations

GPS To Monitor Developing Southwestern Monsoon

Date:
July 8, 2003
Source:
University Of Arizona
Summary:
Atmospheric scientists from the University of Arizona in Tucson and their colleagues at the University of Sonora in Hermosillo, Mexico, are ready for the summer monsoon. With only days to spare before the start of the 2003 monsoon season, UA atmospheric scientists deployed the last of six, state-of-the-art sensor systems at sites in southern Arizona and northwestern Mexico.

Atmospheric scientists from the University of Arizona in Tucson and their colleagues at the University of Sonora in Hermosillo, Mexico, are ready for the summer monsoon.

With only days to spare before the start of the 2003 monsoon season, UA atmospheric scientists deployed the last of six, state-of-the-art sensor systems at sites in southern Arizona and northwestern Mexico. The sensors give them precise measurements of water vapor in the atmosphere every half hour. They are using Global Positioning System (GPS) receivers and other devices to accurately monitor changing humidity in near real time.

Near-real-time information on atmospheric moisture will aid wildfire-fighters, flash-flood and severe-storm forecasters.

"Accurate predictions of rainfall require accurate knowledge of the amount of moisture in the atmosphere and how it changes in time and space," said E. Robert Kursinski, associate professor of atmospheric sciences. "The GPS moisture observations will add to our understanding of moisture flow throughout the year but particularly during the monsoon season. These will lead to improved ability to predict precipitation in our region from hourly to seasonal timescales."

Kursinski, Andrea N. Hahmann, a research scientist professor in atmospheric sciences, graduate student Carlos Minjarez, and others worked to link southern Arizona and Sonora, Mexico, to the larger "SuomiNet" network of moisture-sensing stations. SuomiNet, a collaborative effort that started with the University Corporation for Atmospheric Research (NCAR) in Boulder, Colo., is sponsored by the National Science Foundation (NSF).

Last year the UA team established two moisture-sensing systems, one atop the Gould-Simpson Science Building on the UA campus, the other at Cochise College in Douglas, Ariz. This year, collaborators at the Salt River Project provided a Phoenix site, and University of Sonora colleagues located sensors at their campus in Hermosillo and at a joint university research facility in Puerto Peñasco.

The scientists also recently installed a receiver on Mount Hopkins. "This receiver will aid astronomers making observations (at the 6.5-meter UA/Smithsonian MMTO telescope) as well as give atmospheric scientists detailed measurements of how moisture interacts with mountains to produce monsoonal thunderstorms here in the Southwest," Kursinski said.

The GPS receiver is the primary instrument at each location. Each receiver is supplemented by a package of instruments that measure surface temperature, pressure and humidity.

GPS was extensively used by the military in the Iraq war, Kursinski noted. But the receivers deployed here use GPS signals to precisely measure the amount of humidity in the atmosphere. As humidity builds, additional water molecules make the air denser, so it takes the GPS signal longer to travel from one of the 24 GPS Earth-orbiting satellites to the GPS receiver on the ground. That is, the more water vapor in the atmosphere, the longer the delay in the GPS signal. The researchers can measure the time delay equivalent to roughly one-tenth millimeter extra path length, which translates to about a half-millimeter to one-millimeter precipitation.

One of the great advantages to GPS is its ability to detect moisture through clouds.

"When the monsoon arrives, we get so many clouds which limit the utility of the infrared satellite data," Kursinski said. "The infrared satellite data tells you there's a cloud there, but it can't tell you how much water is there under the clouds. The GPS can tell you that."

"In the past five years, people have realized the need for more frequent weather data, like information we get from this system," Hahmann said. "It is important for planning water resources, for so many applications here in the Southwest. If we knew in advance what kind of monsoon we will get, where it will come from, and when it will get here ˆ that would be very, very useful."

GPS provides crucial observations for monitoring and predicting weather, particularly severe weather, Hahmann said. Scientists recently discovered that GPS moisture measurements significantly improve lightning predictions at NASA's Cape Canaveral launch site, for example.

"We expect the GPS measurements will improve our ability to predict flash floods by identifying rapid 'waves' of water vapor, known among area meteorologists as 'surges', moving up from the Gulf of California, well before they reach us," Hahmann added.

Kursinski, Hahmann and Minjarez plan to further extend the network into Mexico next summer, more than doubling its size in time for the North American Monsoon Experiment (NAME), a June ˆ September 2004 experiment funded by the National Oceanic and Atmospheric Administration and NSF.

NAME objectives are to better understand the basic features of the monsoon and how they vary, to understand how the important our monsoon is to the global water cycle, to provide better measurements of the monsoon, and to better predict monthly-to-seasonal precipitation and water resources.

For NAME, greater coverage by GPS observations will be combined with other radar and balloon-borne measurements together with substantial modeling efforts. The research will yield significant new insights into how our monsoon works and better predictions of its behavior, the UA scientists said.


Story Source:

The above story is based on materials provided by University Of Arizona. Note: Materials may be edited for content and length.


Cite This Page:

University Of Arizona. "GPS To Monitor Developing Southwestern Monsoon." ScienceDaily. ScienceDaily, 8 July 2003. <www.sciencedaily.com/releases/2003/07/030708093046.htm>.
University Of Arizona. (2003, July 8). GPS To Monitor Developing Southwestern Monsoon. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2003/07/030708093046.htm
University Of Arizona. "GPS To Monitor Developing Southwestern Monsoon." ScienceDaily. www.sciencedaily.com/releases/2003/07/030708093046.htm (accessed October 21, 2014).

Share This



More Earth & Climate News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

Newsy (Oct. 20, 2014) — The United Nations says water is a human right, but should it be free? Detroit has cut off water to residents who can't pay, and the U.N. isn't happy. Video provided by Newsy
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) — Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) — Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins