ESRL Quarterly Newsletter - Spring 2010


More news, publications, and honors from NOAA's Earth System Research Laboratory.


Surprise Chemistry

In 2008, ESRL researchers and colleagues testing some equipment in Colorado discovered surprisingly high levels of a chlorine compound normally associated with marine air. Nitryl chloride gas forms at night, when manmade pollutants interact with airborne chloride-containing particles—often from sea spray. But the levels of nitryl chloride found in Boulder were comparable to those expected at oceanic sites, suggesting that chloride-containing particles were more ubiquitous inland than thought.

Now a follow-up study has confirmed that the chemical reactions involved can take place far inland, and that human activities—from coal burning and biomass burning to roadway de-icing—may influence chlorine chemistry in the air above the continental United States. Chlorine chemistry may be involved in the generation of regional smog and other air quality problems, and may also help remove the greenhouse gas methane from the atmosphere.

The new paper, “A large atomic chlorine source inferred from mid‐continental reactive nitrogen chemistry,” appeared March 11 in Nature. ESRL and CIRES authors include Steve Brown, Ann Middlebrook, Nicholas Wagner, Julie Cozic, John Holloway, and William Dubé.

Nature 464, 271-274 (11 March 2010) | doi:10.1038/nature08905; Received 2 October 2009; Accepted 2 February 2010

Physical Sciences Review

Ming Hu speaks with reviewer Ken Leonard during ESRL’s Physical Sciences Review.

Ming Hu speaks with reviewer Ken Leonard during ESRL’s Physical Sciences Review.

During four days in March, researchers from ESRL's Global Systems and Physical Sciences divisions (GSD and PSD) highlighted their accomplishments with talks, posters, and tours for a team of 10 reviewers. The Physical Sciences Review is a quadrennial assessment of the quality, relevance, and performance of research, required of all NOAA research laboratories. Representatives from GSD and PSD related the importance of their group's research accomplishments, technology transfers, and future plans to NOAA's mission and strategic plan.

ESRL's Physical Sciences Reviewers are Michele Rienecker (NASA Goddard Space Flight Center), Gilbert Brunet (RPN Canada), Daniel Cayan (Scripps Institution of Oceanography), George Frederick Jr. (Falcon Consultants LLC), Tsengdar Lee (NASA Office of Earth Science), Margaret (Peggy) LeMone (National Center for Atmospheric Research), Ken Leonard (Federal Motor Carrier Safety Administration), Lars Peter Riishojgaard (NASA Goddard), John Walsh (University of Alaska), Robert Weller (Woods Hole Oceanographic Institution). The team is expected to send an initial report to NOAA by the end of May.

Barrow Snowmelt

Barrow Observatory

Barrow Observatory.

Scientists are scrutinizing data collected at the NOAA/ESRL Barrow Observatory to understand how climate change is affecting the annual snow cycle there, in particular the date when snow melts each spring. Previous studies found that the melt date was occurring earlier than in the past and is influenced by urbanization effects near the village of Barrow, AK. Robert Stone (Global Monitoring Division) has concluded that snow is indeed melting earlier than in the past, but at a less dramatic rate than reported previously. An updated analysis using data collected at the Observatory, which is not prone to the effects of urbanization, suggests that synoptic-scale changes in atmospheric circulation are the primary causes of the observed trend. The changes (so far) cannot be linked directly to greenhouse warming. Rather they appear to be a manifestation of natural climate variations having decadal time scales, Stone said. More:

Web Hits Soar

ESRL's web hits soared late in the day on February 27, from about 30,000 hits per hour (normal) to more than 180,000, according to ESRL webmaster Ann Keane.

Users were searching for web cams that might catch massive waves hitting Hawaii, after Chile's magnitude 8.8 quake. ESRL traffic returned to normal after the tsunami watch was lifted for Hawaii. ESRL hosts web cams watching the Mauna Loa Observatory and others at

A Force for Air

At 6:56 a.m. April 2, a massive unmanned aircraft once used by the U.S. military soared into the air over Southern California, bristling with devices designed to spy on the atmosphere. In the flight operations room at NASA Dryden Flight Research Center, scientists and flight planners—including several from NOAA—exploded into cheers.

ESRL’s GloPac team at NASA Dreyden.

ESRL’s GloPac team at NASA Dreyden, left to right: Brad Hall (GMD), Geoff Dutton (GMD), Jim Elkins (GMD), Laurel Watts (CSD), Eric Hintsa (GMD), David Fahey (CSD), Phil Hall (NOAA Corps). Not pictured: RuShan Gao (CSD).

The aircraft was a 116-foot-wingspan unmanned aircraft system, or UAS, called a Global Hawk, and it soared for more than six hours over southern California that day, in its first science test flight. Onboard were nearly a dozen instruments to collect precise information about the parcels of air the craft would encounter—air enriched in chemicals that deplete Earth's protective ozone layer and with greenhouse gases.

The full science mission, dubbed GloPac for Global Hawk Pacific, should begin later this month, and will focus on measuring levels of atmospheric constituents important in climate change and stratospheric ozone depletion.

“Our planning and preparations paid off with good instrument performance on the first flight,” said ESRL's David Fahey (Chemical Sciences Division), who is co-mission scientist on GloPac. Fahey said he had his colleagues think of UAS as “a hybrid” of satellites and aircraft, and in the future, they imagine, fleets of UAS could prowl the atmosphere, gathering data to help weather forecasters, climate and air quality researchers, and others.

NASA and NOAA engineers and colleagues from several academic and private research institutions have spent the last 20 months readying the Global Hawk for its first science campaign, which will eventually involve four or five flights over the Pacific Ocean from the tropics up to the Arctic. Those flights will be long—the aircraft can fly for up to 30 hours, reaching places and distances unobtainable with a more typical research airplane, Fahey said.

Mission scientists are blogging about the campaign at, and more information is available at:


Daniel Wolfe (Physical Sciences) and Richard McLaughlin (Chemical Sciences) received 2009 Distinguished Career Awards, announced in March by NOAA Administrator Jane Lubchenco. Wolfe, who has worked for NOAA in Boulder since 1975, won for his “long-term stewardship of the Boulder Atmospheric Observatory and its recent revitalization as a world-class climate observing facility.” McLaughlin won “for sustained, outstanding, and diverse contributions to the success of airborne sampling instruments requiring creative design skills and mechanical craftsmanship.” McLaughlin has worked for NOAA in Boulder since 1979.

Several ESRL scientists won 2009 Bronze Medals, also announced in March: Klaus Weickmann (Physical Sciences) was part of a Bronze team lauded for issuing skillful forecasts of weather and climate hazards based on an ensemble forecast system. Bradley Hall (Global Monitoring) won a Bronze medal “for his contributions to the accurate calibration of greenhouse and other important atmospheric gases for NOAA, the nation, and the global community.” Charles Brock, Daniel Murphy and Thomas Ryerson (Chemical Sciences) shared the medal with two colleagues from NOAA's Pacific Marine Environmental Laboratory, for their leadership of field missions during the International Polar Year, to study the fast-changing Arctic. Stephen Weygandt, Stanley Benjamin, and John M. Brown (Global Systems) shared a Bronze with colleagues from the National Weather Service, for developing an “operational radar reflectivity assimilation technique and improving convective storm forecasting.” Daniel Gottas, Paul Neiman, Allen White (Physical Sciences), and Seth Gutman (Global Systems) shared a Bronze with a National Weather Service colleague “for innovative contributions to the development of the Coastal Atmospheric River Monitoring and Early Warning System.”

Robert Banta (Chemical Sciences) and Randy Dole (Physical Sciences) were named Fellows of the American Meteorological Society. Graham Feingold (Chemical Sciences) coauthored chapters in two books that received awards from the Atmospheric Science Librarians International, presented during the American Meteorological Society annual meeting. Clouds in the perturbed climate system: their relationship to energy balance, atmospheric dynamics, and precipitation won the ASLI Choice Award. Aerosol pollution impact on precipitation: a scientific review earned an honorable mention.

A proposal by Carol Knight (ESRL Director's Office) was one of 12 selected for a NOAA Preserve America Initiative grant, among more than 70 applicants. Knight will work with middle school students to produce YouTube-type oral history videos about NOAA-Boulder scientists and science.

David Parrish (Chemical Sciences) was invited to give the 19th annual Harold I. Schiff lecture in December last year, at York University in Toronto, Canada.

A paper authored by A.R. Ravishankara, John Daniel, and Robert Portmann (Chemical Sciences) was named one of Nature's top ten research highlights of 2009 (Nature editors select the best papers published in other journals). Ravishanakara, Daniel, and Portmann published “Nitrous Oxide (N2O): The Dominant Ozone-Depleting Substance Emitted in the 21st Century” in Science in October.

A.R. Ravishankara (Chemical Sciences Division Director) was invited to be the 2010 Hinshelwood Lecturer at the Department of Chemistry of Oxford University. The lecturer—a distinguished chemist or physicist from overseas—spends about two weeks delivering lectures at several institutions in the United Kingdom.

Susan Solomon (Chemical Sciences) and colleagues in Switzerland and France co-authored a paper identified by Thomson Reuters Essential Science Indicators SM as a “New Hot Paper” in the field of geosciences, meaning it was one of the most-cited papers in geoscience published during the past two years. The article, “Irreversible climate change due to carbon dioxide emissions,” was published in the Proceedings of the National Academy of Sciences in January 2009.