EOL

EOL Seminar Series - Philip Brown (EUFAR)

Observations-Based Research in the Met Office: Current Activities and Future Plans

Philip BrownMet OfficeEuropean Facility for Airborne Research (EUFAR)

EOL Seminar Series - Holger Vömel (ISF/EOL)

Stratospheric Water Vapor Processes and Trends from In Situ Observations

In-situ observations of water vapor in the stratosphere and in the tropopause region are an important tool to study trends and processes of stratospheric water vapor.

EOL Seminar Series - Joseph Cione (NOAA)

NOAA’s use of the Coyote UAS in Hurricane Edouard to enhance basic understanding and improve model physics

A meeting for storm-driven science

October 22, 2014 | Among the world’s varied climates, two populous midlatitude areas get an especially big helping of large-scale extreme rainfall: eastern Asia and central-to-eastern North America. Experts from both continents met at NCAR on September 15–18 to discuss promising avenues of research that could lead to improvements in predicting hurricanes, floods, and other phenomena affecting billions of people. The Tenth International Conference on Mesoscale Convective Systems (ICMCS) arrived in the Western Hemisphere for only the second time in the meeting’s 15-year history. Sponsored by a nongovernmental organization called the East Asia Weather Research Association, the ICMCS rotates among five member nations: China, Japan, Korea, Taiwan, and the United States. Hurricanes, typhoons, and cyclones The ICMCS’s mission is broader than its title might suggest. Originally, the meetings focused on mesoscale convective systems, huge clusters of thunderstorms that often dump torrential rain. Over the last decade, the meeting has broadened to incorporate related phenomena and emerging technologies that can help observe and model such systems. A growing priority: the tropical cyclones known as hurricanes in North America, typhoons in east Asia, and cyclonic storms in India.  Fumie Murata (University of Kochi) confers with Satoshi Okawara (Japan Radio Company) at the ICMCS meeting in Boulder. (©UCAR. Photo by Bob Henson.) “Tropical cyclones are big issues for east Asia countries, so they’ve gotten more attention from ICMCS in recent years,” says NCAR’s Wen-chau Lee. He shared organizational duties for the Boulder meeting with fellow NCAR scientist Ying-Hwa “Bill” Kuo and David Jorgensen (NOAA National Severe Storms Laboratory). Although the United States has a well-deserved reputation for wild weather—the world’s heaviest one-hour rainfall occurred in Missouri, and 43 inches of rain once fell in 24 hours near Houston—Asia is no slouch when it comes to tropical cyclones, heavy rainfall, and flooding. NASA astronaut Reid Wiseman captured this image of Super Typhoon Vongfong from the International Space Station as the storm churned across the northwest Pacific Ocean on October 9, 2014. Vongfong was the world's strongest tropical cyclone of the year thus far, with estimated winds reaching 180 mph. (NASA image courtesy Reid Wiseman.) “In fact, these events are often more frequent and severe in Asia than their U.S. counterparts,” says Lee. One of the highlights of this year’s meeting in Boulder was the presentation of results from several field experiments over the last few years that focused on processes influencing Asian and North American weather. These studies, including TiMREX, T-PARC, ITOP, and DYNAMO, are helping scientists form a deeper understanding of how processes such as the Madden-Julian Oscillation transfer energy and moisture northward from the tropics and eastward across the Northern Hemisphere. The meeting drew nearly 100 participants from the five nations behind ICMCS, including about 20 graduate students. “These students represent the next generation of our scientific work force,” notes Lee. Writer: Bob Henson, NCAR/UCAR Communications Collaborating institutions:National Center for Atmospheric ResearchUniversity Corporation for Atmospheric Research Funders:National Science Foundation

EOL Seminar Series - Wen-Chau Lee (RSF/EOL)

Distance Velocity Azimuth Display (DVAD) – New interpretation and analysis of Doppler velocity

Wen-Chau LeeRemote Sensing FacilityEarth Observing Laboratory

EOL Seminar - Lou Lussier (EOL/RAF)

Case studies of tropical cyclogenesis of within the critical layer of easterly waves: typhoon Nuri (2008) and hurricane Sandy (2012)

Lou LussierResearch Aviation FacilityEarth Observing Laboratory

EOL Seminar - Ebba Dellwik & Jakob Mann

Can coherant continuous-wave doppler lidars be utilized for in-situ instrument calibration?

Ebba Dellwik & Jakob MannDTU Wind Energy, Denmark

EOL Seminar Series - Annette Foerster (Univ. of Hawaii)

Airborne radar observations of tropical cyclone eyewalls

Annette FoersterDepartment of Atmospheric SciencesUniversity of Hawaii at Manoa

Where's the atmosphere's self-cleaning power?

September 12, 2014 | In a finding that could alter how scientists quantify emissions of certain pollutants, a new study in Nature concludes that the self-cleaning power of the atmosphere does not differ substantially between the northern and southern hemispheres. The finding was surprising, as model simulations generally show that the hydroxyl molecule (OH)—the dominant “detergent” of the atmosphere that removes many pollutants by oxidizing them—is more common in the Northern Hemisphere. “This suggests we still have more to learn about this aspect of atmospheric chemistry,” said NCAR scientist Britton Stephens, a co-author of the paper. The Sun rises over Antarctica during HIPPO with the wing of the NSF/NCAR HIAPER research aircraft in the foreground. During a three-year field project, HIPPO researchers sent the Gulfstream V jet from the Arctic to the Antarctic, gathering the most extensive airborne sampling of carbon dioxide and other greenhouse gases to date. Data from HIPPO has contributed to new findings about the geographic distribution of the hydroxyl molecule, which removes many natural pollutants from the atmosphere. (©UCAR. Photo by Andrew Watt. This image is freely available for media & nonprofit use.) Because massive amounts of nitrogen oxides are emitted in the Northern Hemisphere by motor vehicles, industry, and other human-related activities concentrated there, OH has been thought to be more common in that region. The nitrogen oxides promote the formation of ozone, which in turn can react with water vapor molecules in the presence of sunlight to form OH. OH is highly difficult to measure because it exists in low concentrations and lasts for just about a second on average before reacting with pollutants and other gases. The new study, led by Prabir Patra of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), inferred OH concentrations by using measurements of methyl chloroform, a human-made chemical that is chiefly removed from the atmosphere by OH. The measurements came from two long-term, ground-based observation networks as well as from a 2009–2011 field project that deployed an advanced research aircraft owned by the National Science Foundation and operated by NCAR. The HIAPER Pole-to Pole Observations project, or HIPPO, flew from the Arctic to Antarctic, taking detailed observations of the atmosphere at a range of altitudes. The new study also drew on an advanced JAMSTEC atmospheric chemistry model. The results indicate that the northern/southern hemisphere ratio of OH is nearly equivalent at about .97, plus or minus .12. In contrast, state-of-the-art models have predicted an OH concentration that is 13-42% higher in the Northern Hemisphere. The ratio is significant as scientists have relied on OH concentration to estimate emissions of certain gases, such as methane and carbon monoxide. The estimates of these emissions in the Northern Hemisphere may need to be revised if concentrations of OH are approximately the same as in the Southern Hemisphere, the authors said. P. K. Patra, M.C. Krol, S. A. Montzka, T. Arnold, E. L. Atlas, B.R. Lintner, B.B. Stephens, B. Xiang, J. W. Elkins, P. J. Fraser, A. Ghosh, E. J. Hintsa, D. F. Hurst, K. Ishijima, P. B. Krummel, B.R. Miller, K. Miyazaki, F.L. Moore, J. Mühle, S. O’Doherty, R.G. Prinn, L.P. Steele, M. Takigawa, . J. Wang, R.F. Weiss, S.C. Wofsy, and D. Young, Observational evidence for interhemispheric hydroxyl-radical parity, Nature, doi:10.1038/nature13721 Writer/contactDavid Hosansky, NCAR & UCAR Communications Collaborating institutionsJAMSTEC, Tohoku University, Wageningen University, National Oceanic and Atmospheric Administration, Scripps Institution of Oceanography, University of Miami, Rutgers (The State University of New Jersey), National Center for Atmospheric Research, Harvard University, Centre for Australian Weather and Climate Research (Commonwealth Scientific and Industrial Research Organisation, or CSIRO), National Institute of Polar Research, Cooperative Institute for Research in the Environmental Sciences, University of Bristol, Massachusetts Institute of Technology, Georgia Institute of Technology FundersJapan Society for the Promotion of Science/Grants-in-Aid for Scientific ResearchJapan Ministry of Education, Culture, Sports, Science and TechnologyNational Science FoundationNASAEuropean Union FP7 project PEGASOSNational Oceanic and Atmospheric AdministrationCSIROU.K. Department of Energy and Climate Change                  

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