Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Colorado mountain hail may disappear in a warmer future

09.01.2012
NOAA-led study shows less hail, more rain in region's future, with possible increase in flood risk

Summertime hail could all but disappear from the eastern flank of Colorado's Rocky Mountains by 2070, according to a new modeling study by scientists from NOAA and several other institutions.

Less hail damage could be good news for gardeners and farmers, said Kelly Mahoney, Ph.D., lead author of the study and a postdoctoral scientist at NOAA's Earth System Research Laboratory in Boulder, Colo. But a shift from hail to rain can also mean more runoff, which could raise the risk of flash floods, she said.

"In this region of elevated terrain, hail may lessen the risk of flooding because it takes a while to melt," Mahoney said. "Decision makers may not want to count on that in the future."

For the new study, published this week in the journal Nature Climate Change, Mahoney and her colleagues used "downscaling" modeling techniques to try to understand how climate change might affect hail-producing weather patterns across Colorado.

The research focused on storms involving relatively small hailstones (up to pea-sized) on Colorado's Front Range, a region that stretches from the foothill communities of Colorado Springs, Denver and Fort Collins up to the Continental Divide. Colorado's most damaging hailstorms tend to occur further east and involve larger hailstones not examined in this study.

In the summer on the Front Range, precipitation commonly falls as hail above an elevation of 7,500 feet. Decision makers concerned about the safety of mountain dams and flood risk have been interested in how climate change may affect the amount and nature of precipitation in the region.

Mahoney and her colleagues began exploring that question with results from two existing climate models that assumed that levels of climate-warming greenhouse gases will continue to increase in the future (for instance, carbon dioxide, which is at about 390 parts per million today, increases in the model to 620 ppm by 2070).

But the weather processes that form hail – thunderstorm formation, for example – occur on much smaller scales than can be reproduced by global climate models. So the team "downscaled" the global model results twice: first to regional-scale models that can take regional topography and other details into account (this step was completed as part of the National Center for Atmospheric Research's North American Regional Climate Change Assessment Program). Then, the regional results were further downscaled to weather-scale models that can simulate the details of individual storms and even the in-cloud processes that create hail.

Finally, the team compared the hailstorms of the future (2041-2070) to those of the past (1971-2000) as captured by the same sets of downscaled models. Results were similar in experiments with both climate models.

"We found a near elimination of hail at the surface," Mahoney said.

In the future, increasingly intense storms may actually produce more hail inside clouds, the team found. However, because those relatively small hailstones fall through a warmer atmosphere, they melt quickly, falling as rain at the surface or evaporating back into the atmosphere. In some regions, simulated hail fell through an additional 1,500 feet (~450 meters) of above-freezing air in the future, compared to the past.

The research team also found evidence that extreme precipitation events across all of Colorado may become more extreme in the future, while changes in hail patterns may depend on hailstone size -- results that are being explored in more detail in ongoing work.

Mahoney's postdoctoral research was supported by the PACE program (Postdocs Applying Climate Expertise) administered by the University Corporation for Atmospheric Research and funded by NOAA, the Bureau of Reclamation and the Western Water Assessment. PACE connects young climate scientists with real-world problems such as those faced by water resource managers.

"With climate change, we are examining potential changes in the magnitude and character of precipitation at high elevations," said John England, Ph.D., flood hydrology specialist at the Bureau of Reclamation in Denver, Colo. "The Bureau of Reclamation will now take these scientific results and determine any implications for its facilities in the Front Range of Colorado."

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.

Co-authors of the new paper, "Changes in hail and flood risk in high-resolution simulations over the Colorado Mountains," include Michael Alexander (NOAA/Earth System Research Laboratory); Gregory Thompson (National Center for Atmospheric Research) and Joseph Barsugli and James Scott (NOAA/Cooperative Institute for Research in Environmental Sciences, CIRES).

Katy Human | EurekAlert!
Further information:
http://www.noaa.gov

More articles from Earth Sciences:

nachricht From volcano's slope, NASA instrument looks sky high and to the future
27.04.2017 | NASA/Goddard Space Flight Center

nachricht Penn researchers quantify the changes that lightning inspires in rock
27.04.2017 | University of Pennsylvania

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>