Featured Research

from universities, journals, and other organizations

Improved Water Vapor Sensor Takes To The Skies

Date:
June 16, 2005
Source:
National Center for Atmospheric Research/University Corporation for Atmospheric Research
Summary:
A new water vapor sensor developed partly at the University Corporation for Atmospheric Research will improve a wide range of weather forecasts to make flying safer, allow airlines to expand routes, provide alternate landing options, and save fuel. The new data can also verify computer model projections of climate change.

This tiny diode laser cell, paired with a UCAR-developed air sampler, provides an economical yet highly accurate alternative to weather balloons or satellites for collecting atmospheric water vapor data.
Credit: Photo courtesy SpectraSensors, Inc.

Currently water vapor data is gathered by an older style of sensor using a thin-film capacitor. These sensors are launched on weather balloons every 12 hours from stations around the country. Satellites also gather water vapor data, but at low vertical resolution. The WVSS II aboard commercial flights will gather data more often, at higher vertical resolution, and at lower cost than satellites and balloons.

"Water vapor sounds boring," says recently retired UCAR scientist Rex Fleming, who designed the innovative air sampler, "but it's essential to almost everything that happens in the atmosphere." Better water vapor data from around the U.S. and the world can improve forecasts of thunderstorms, microbursts, turbulence, fog, ceiling visibility, rotating wakes from other aircraft, snow and ice storms, and year-round precipitation, he says.

Water vapor also plays an important role in small storms that develop quickly and wreak havoc with airline schedules and safety. The Federal Aviation Administration estimates these storms can cost the aviation industry more than $1 billion annually.

Improved aviation weather forecasts can make flying safer, allow airlines to expand the number and location of routes, provide alternate landing options, and save fuel. Over the long term, the new data can verify computer model projections of climate change, which indicate water vapor steadily increasing in Earth's atmosphere. As a greenhouse gas, water vapor is 10 times more potent than carbon dioxide and its increase is a key factor in the rising global temperatures appearing in the models.

The FAA certified the WVSS II for commercial aircraft flights last December. Preliminary results show the WVSS II data are highly consistent with the balloon data up to 35,000 feet. This month's tests should lead to verification of the sensing system for other uses by forecasters, air traffic controllers, and research scientists.

"In a typical year, more water in the form of vapor and clouds flows over the dry state of Arizona than flows down the Mississippi River," says Fleming. "Yet we have not had a sensing system to collect accurate water vapor data frequently enough to be really useful for forecasts." Commercial aircraft can fill a critical gap in atmospheric observations by gathering accurate data throughout the global atmosphere, he adds.

Mounted flush on the outside of the plane, Fleming's sampler channels air into the measurement cell housed in a casing the size of a cigar box just inside the aircraft shell. The sampler weeds out most ice crystals, particles, rain, and other distractions to improve the sensitivity of the measurement. The laser frequency itself sees only water vapor in the air flow.

UPS has provided wind and temperature data to meteorologists from more than half its air fleet since 1994. In 1997, UPS added water vapor information, expressed as relative humidity, from a first-generation test sensor installed on 30 aircraft. The new second-generation sensors are expected to be far more accurate and reliable, especially at higher altitudes and colder temperatures.

Southwest Airlines will begin flying the system when further government funds are available. The German Weather Service is in the process of certifying the sensor, and Lufthansa will be installing four units on commercial flights later this year. New Zealand, Australia, and South Africa will collaborate with the German Weather Service on an initial purchase of ten units.

The FAA's Aviation Weather Research Program and NOAA's Office of Global Programs funded development of the WVSS II. The diode laser cell was designed by Randy May of SpectraSensors, the manufacturer of the product.



Story Source:

The above story is based on materials provided by National Center for Atmospheric Research/University Corporation for Atmospheric Research. Note: Materials may be edited for content and length.


Cite This Page:

National Center for Atmospheric Research/University Corporation for Atmospheric Research. "Improved Water Vapor Sensor Takes To The Skies." ScienceDaily. ScienceDaily, 16 June 2005. <www.sciencedaily.com/releases/2005/06/050616060456.htm>.
National Center for Atmospheric Research/University Corporation for Atmospheric Research. (2005, June 16). Improved Water Vapor Sensor Takes To The Skies. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2005/06/050616060456.htm
National Center for Atmospheric Research/University Corporation for Atmospheric Research. "Improved Water Vapor Sensor Takes To The Skies." ScienceDaily. www.sciencedaily.com/releases/2005/06/050616060456.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Weather Kills 2K A Year, But Storms Aren't The Main Offender

Weather Kills 2K A Year, But Storms Aren't The Main Offender

Newsy (July 30, 2014) Health officials say 2,000 deaths occur each year in the U.S. due to weather, but it's excessive heat and cold that claim the most lives. 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:
from the past week

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