News
ESRL Scientists Receive CIRES Awards at Annual Meeting
entered on 21st Apr, 2009 01:55:57 PM MSTThirteen ESRL scientists received significant awards at the Fourth Annual All-Institute Symposium of the Cooperative Institute for Research in Environmental Sciences (CIRES), held on April 1, 2009.
In the Chemical Sciences Division, John Holloway received a 2009 Outstanding Performance Award in Science and Engineering for his work in developing and applying a state-of-the-art instrument that uses vacuum UV to measure carbon monoxide (CO) from aircraft. He successfully engineered the instrument so that it could be deployed in a pod mounted under the wing of the NOAA WP-3D research aircraft, a design that enabled other investigators to use the scarce space aboard the aircraft for their instruments. He mentored a graduate student from the University of Tokyo in this work. John has served as a principal investigator in 13 missions of the P3, during which he has had "end to end" involvement: managing the operation, deployment, and repair of the instrument, analyzing and archiving the data; and publishing the results from the instrument. His work has investigated air pollution and photochemistry related to air quality, contributing to the Air Quality Program of NOAA's Weather and Water Mission Goal.
Also in the Chemical Sciences Division, Christine Ennis received a CIRES Director's Award for her work on the Climate Change Science Program's "Synthesis and Assessment Product 2.4," which dealt with ozone-depleting substances and the stratospheric ozone layer. Her NOAA colleagues were recognized with the NOAA Administrator's Award.
Other ESRL colleagues who received awards were: Andrew Crotwell, Geoff Dutton, Molly Heller, Debra Mondeel, Carolina Siso, and Kelly Sours (all of the Global Monitoring Division), who received the CIRES Silver Medal for their contributions to the Annual Greenhouse Gas Index (AGGI). Also in GMD, Sonja Wolter, Doug Guenther, and Fred Moore received a CIRES Science and Engineering Award for their contributions in developing a programmable flask package whole air sampler, and Molly Heller received a CIRES Service Award for her contributions in logistics for the flask program. Sergey Matrosov of the Physical Sciences Division received a Science and Engineering Award for his use of millimeter wavelength radar to study the properties of clouds and precipitation.
Some Climate Cooling Proposals Could Crimp Solar Power Output
entered on 27th Mar, 2009 03:47:26 PM MSTIncreasing the number of particles in Earth's stratosphere could significantly reduce the output from large solar electric power generating plants, according to a study by ESRL Chemical Sciences Division scientist Dan Murphy. The study was published on March 11 in the online version of Environmental Science and Technology.
Murphy showed that stratospheric particles change both the amount and the nature of the sunlight that strikes the Earth. Though a fraction of the incoming sunlight bounces back to space (the cooling effect), a much larger amount becomes "diffuse" or scattered light that cannot be used by concentrating solar collectors. The study showed that on average, for every 1 watt of sunlight the particles reflect away from the Earth, another 3 watts of direct sunlight are converted to diffuse sunlight. Solar power generation systems using parabolic or other concentrating methods can only use direct sunlight and would be affected most. Flat photovoltaic or heating panels would be affected much less.
Murphy verified his calculations using long-term NOAA observations of direct and diffuse sunlight before and after the 1991 eruption of Mt. Pinatubo, which released gases and particles that led to a large increase in stratospheric particles. After the eruption, the power output of Solar Electric Generating Systems plants in California fell by 10 to 20%, depending on the measure used for electrical output. The amount of particles added by the Mt. Pinatubo eruption was similar to amounts in some deliberate enhancement proposals.
Murphy's calculations and the Pinatubo eruption reveal a perhaps surprising sensitivity. Murphy explains, "Stratospheric particles have a disproportionately large effect on concentrating solar systems."
Although Murphy considered only stratospheric particles in the study, scattering by clouds or particles in the lower atmosphere would also reduce direct sunlight. Other consequences of the changes from direct to diffuse sunlight, such as effects on ecosystem productivity, were not examined in the study.
Background: "Direct" sunlight comes straight from the sun and casts sharp shadows. "Diffuse" sunlight comes from the sky in all directions. Particles preferentially scatter light in the forward direction. This causes more of the light that hits a tiny particle to reach the Earth as diffuse light than to bounce away from the Earth.
Significance: The result means that so-called "geoengineering" proposals that would deliberately add particles to the stratosphere to help cool the planet would have unintended consequences for one of the alternative energy sources that is expected to be a part of the transition away from fossil fuel-based sources in the coming decades.
Citation: Effect of stratospheric aerosols on direct sunlight and implications for concentrating solar power, Environmental Science and Technology, doi:10.1021/es8802206b, 2009. (web publication date: 11 March 2009) Author: Daniel M. Murphy, Chemical Sciences Division, Earth System Research Laboratory, NOAA.
Study Quantifies Pollutant Emissions from Ships
entered on 27th Mar, 2009 01:05:38 PM MSTA new study published in February in the Journal of Geophysical Research by CIRES and ESRL/Chemical Sciences Division scientist Dan Lack and colleagues finds that globally, commercial ships emit as much particulate matter (PM) pollutants into the air as nearly half the cars on the road. Their study is the first to provide a global estimate of shipping's total contribution to air particle pollution based on direct measurements of emissions. An earlier (2008) study by Lack and colleagues focused exclusively on soot.
Since more than 70% of shipping traffic takes place within 250 miles of the coastline, this is a significant health concern for coastal communities, notes Lack. These particles also affect climate. Particles from shipping have a global cooling effect and mask, by at least five times, the global warming resulting from the carbon dioxide from ships, which makes up roughly 3% of human-emitted carbon dioxide. Shipping also contributes almost 30% of smog-forming nitrogen oxide gases.
During the summer of 2006, Lack and colleagues, aboard the NOAA research vessel, the Ronald H. Brown, analyzed the exhaust from over 200 commercial shipping vessels -- including cargo ships, tankers, and cruise ships -- in the Gulf of Mexico, Galveston Bay, and the Houston Shipping Channel. They estimated that globally ships emit 0.9 teragrams, or about 2.2 million pounds, of particle pollution each year.
The researchers also examined the chemistry of particles in ship exhaust, in order to understand what makes ships such hefty polluters. They found that emissions of sulfates -- the same particles associated with diesel-engine cars and trucks, which motivated improvements in on-road vehicle fuel standards -- vary with the concentration of sulfur in ship fuel. Globally, fuel sulfur content is capped under the International Convention for the Prevention of Pollution From Ships. As a result of the cap, some ships use "cleaner," low-sulfur fuels, while others continue to use the high-sulfur counterparts.
Yet, sulfates make up just under half of shipping's total particle emissions, according to the study. Organic pollutants and sooty, black carbon, which make up the other half of emissions, are not directly targeted by today's regulations. Emissions of these particles, the study found, depend on the operating speed of the engine and the amount of lubricating oil needed to deal with wear and tear from burning less-refined fuels. Engines burning 'cleaner,' low-sulfur fuels tend to require less lubrication. So fuel regulations have an indirect effect on the organic particles emitted.
One surprising result of burning low-sulfur fuels: while total particle emissions shrink, the time the particles spend airborne -- and pose a risk to human health and affect climate-- appears to increase. Lack and colleagues found that the organic and black carbon portion of ship exhaust is less likely to form cloud droplets. As a result, these particles remain suspended for longer periods of time before being washed to the ground through precipitation.
Particles from shipping are thought to mask, by at least 5 times, the global warming by ship carbon dioxide, which makes up roughly 3% of human-emitted carbon dioxide. Shipping also contributes almost 30% of smog-forming nitrogen oxide gases.
Citation for paper: Particulate emissions from commercial shipping: Chemical, physical, and optical properties, Journal of Geophysical Research, vol 114, D00F04, doi: 10.1029/2008JD011300, 2009.
Authors:
Daniel A. Lack, Cooperative Institute for Research in Environmental Sciences and Chemical Sciences Division, Earth System Research Laboratory, NOAA.
James J. Corbett, University of Delaware.
Timothy Onasch, Aerodyne Research Inc.
Brian Lerner, Cooperative Institute for Research in Environmental Sciences and Chemical Sciences Division, Earth System Research Laboratory, NOAA.
Paola Massoli, Cooperative Institute for Research in Environmental Sciences and Chemical Sciences Division, Earth System Research Laboratory, NOAA.
Patricia Quinn, Pacific Marine Environmental Laboratory.
Timothy S. Bates, Pacific Marine Environmental Laboratory.
David S. Covert, University of Washington.
Derek Coffman, Pacific Marine Environmental Laboratory.
Berko Sierau, University of Washington, now at Swiss Federal Institute of Technology.
Scott Herndon, Aerodyne Research, Inc.
James Allan, University of Manchester.
Tahlee Baynard, CIRES and NOAA/ESRL/CSD, now at Lockheed Martin Coherent Technologies.
Edward Lovejoy, Chemical Sciences Division, Earth System Research Laboratory, NOAA.
A.R. Ravishankara, Chemical Sciences Division, Earth System Research Laboratory, NOAA.
Eric Williams, Cooperative Institute for Research in Environmental Sciences and Chemical Sciences Division, Earth System Research Laboratory, NOAA.
2008 Arctic Haze Linked to Faraway Wildfires, Agricultural Burning
entered on 5th Feb, 2009 05:01:44 PM MSTA study by researchers in ESRL CSD and GMD and CIRES and published on 30 January in Geophysical Research Letters has been named as one of the "Editors' Highlights" for that issue. Lead Author Carsten Warneke (CSD/CIRES) and coauthors showed that the 2008 springtime "Arctic haze" over northern Alaska and the Arctic region had unexpectedly high signatures of faraway sources: wildfires and biomass burning activities occurring in Asia. They used data from the April 2008 Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC) airborne field experiment, based in Fairbanks, Alaska. Chemical and meteorological instrumentation onboard the NOAA WP-3D aircraft gathered data on more than 50 plumes that were encountered during the six research flights over northern Alaska and the Arctic sea ice. The chemical composition of the plumes and transport modeling led to the authors' finding that most of the plumes were emitted by forest fires in southern Siberia and by agricultural burning in Kazakhstan-southern Russia. An unexpected finding was that these biomass burning plumes were the dominant aerosol and gas-phase features encountered during the April time period of the mission. This was perhaps because the fire season in Siberia started earlier than usual, and therefore transport of the fires' emissions to the Arctic was unusually efficient.
Background: Arctic haze consists of gas-phase and particle pollutants that are likely produced from emissions of pollutants from Europe, Asia, and North America and by episodic plumes released from biomass burning and wildfires. It has been a regular feature at northern latitudes since the 1950s. Slow removal processes for the pollutants leads to the persistence of Arctic haze. The light-absorbing properties of smoke and haze can affect Arctic climate through direct warming of the troposphere, acceleration of snow melting by the absorption of radiation by soot deposited on the surface, and changes in the climate-related properties of clouds. The ARCPAC mission was focused on investigating the chemical, optical, and microphysical characteristics of aerosol particles and gas-phase species in the Arctic springtime to determine the sources (industrial, urban, biomass/biofuel burning, dust, sea salt) of those components.
Significance: The presence of the biomass burning smoke in the surface layer over Arctic sea ice and snow-covered land suggests that light-absorbing aerosols could be efficiently deposited to the snow/ice surface, potentially reducing surface albedo and thereby affecting the radiation balance in the region. Biomass burning is a large source of aerosols in the Arctic, but usually occurs in the late spring or early summer when transport to the Arctic is not as efficient. Earlier starts to the fire season, possibly because of warming in the boreal regions, could give rise to a feedback loop by shifting the timing (and increasing the magnitude) of the impacts on forest fires on Arctic climate.
Citation: Warneke, C., R. Bahreini, J. Brioude, C.A. Brock, J.A. de Gouw, D.W. Fahey, K.D. Froyd, J.S. Holloway, A. Middlebrook, L. Miller, S. Montzka, D.M. Murphy, J. Peischl, T.B. Ryerson, J.P. Schwarz, J.R. Spackman, and P. Veres (2009), Biomass burning in Siberia and Kazakhstan as an important source for haze over the Alaskan Arctic in April 2008, Geophys. Res. Lett., 36, L02813, doi:10.1029/2008GL036194.
Author affiliations:
ESRL CSD: Brock, Fahey, Middlebrook, Ryerson, Murphy
ESRL CSD and CIRES: Warneke, Bahreini, Brioude, de Gouw, Froyd, Holloway, Peischl, Schwarz, Spackman, Veres
ESRL GMD: Montzka
ESRL GMD and CIRES: Miller
More information: http://www.agu.org/cgi-bin/highlights/highlights.cgi?action=show&doi=10.1029/2008GL036194&jc=gl
New Study Shows Climate Change Largely Irreversible
entered on 26th Jan, 2009 01:28:14 PM MSTA new scientific study to be published in the Proceedings of the National Academy of Sciences this week reaches a powerful conclusion about the climate change caused by future increases of carbon dioxide (CO2): to a large extent, there's no going back.
The pioneering study, led by senior scientist Susan Solomon of ESRL's Chemical Sciences Division, shows how changes in surface temperature, rainfall, and sea level are largely irreversible for more than 1000 years after carbon dioxide emissions are completely stopped. If carbon dioxide is allowed to rise to 450-600 parts per million from its current value of 385 parts per million, and then CO2 emissions completely cease, the results would include persistent decreases in dry-season rainfall that are comparable to the 1930s North American "Dust Bowl" in zones including southern Europe, northern Africa, southwestern North America, southern Africa, and western Australia. The study notes that decreases in rainfall that last not just for a few decades but over centuries are expected to have a range of impacts that differ by region, including human water supplies, effects on dry-season wheat and maize agriculture in regions of rain-fed farming such as Africa, increased fire frequency, ecosystem change, and desertification.
The scientists emphasize that increases in CO2 that occur in this century essentially "lock in" sea level rise that would slowly follow in the next thousand years. Considering just the expansion of warming ocean waters as a lower bound, the authors find that the irreversible global average sea level rise by the year 3000 would be at least 0.4 - 1.0 meters if CO2 peaks at 600 parts per million, and about double that amount if CO2 peaks at 1000 parts per million. Rising sea levels would cause "...irreversible commitments to future changes in the geography of the Earth, since many coastal and island features would ultimately become submerged," the authors write.
Added carbon dioxide and its climate effects linger because of the ocean.
"In the long run, both carbon dioxide loss and heat transfer depend on the same physics of deep-ocean mixing. The two work against each other to keep temperatures almost constant for more than a thousand years, and that makes carbon dioxide unique among the major climate gases," said Solomon.
Geoengineering to remove carbon dioxide from the atmosphere was not considered in the study. "Ideas about taking the carbon dioxide away after the world puts it in have been proposed, but right now those are very speculative," said Solomon.
The authors relied on measurements as well as many different models to support the understanding of their results. They focused on drying of particular regions and on thermal expansion of the ocean because observations suggest that humans are contributing to changes that have already been measured.
Besides Solomon, the study's authors are Gian-Kasper Plattner and Reto Knutti of ETH Zurich, Switzerland, and Pierre Friedlingstein of Institut Pierre Simon Laplace, Gif-Sur-Yvette, France.
Background: It has long been known that some of the carbon dioxide emitted by human activities stays in the atmosphere for thousands of years, but the new study advances the understanding of how this affects the climate system. The authors used measurements and several models to examine the consequences of allowing carbon dioxide to build up to several different peak levels beyond present-day concentrations, and then completely halting the emissions after the peak. The authors found that the scientific evidence is strong enough to quantify some irreversible climate impacts, including rainfall changes in certain key regions, and global sea level rise.
Significance: This study gives a clear demonstration that the climate change that takes place due to increases in carbon dioxide is largely irreversible, and would have large consequences for agriculture, ecosystems, and coastal environments.
Solomon Addresses Senate and House Staff at Climate Seminars
entered on 15th Jan, 2009 02:04:11 PM MSTOn Friday, January 9th, CSD senior scientist Susan Solomon was an invited panelist at two seminars on Capitol Hill, "Climate Change: Intersections of Science and Policy." A morning seminar on the Senate side was followed by an afternoon seminar on the House side. The seminars were aimed at aiding policy makers in their discussions of scientific issues related to climate.
Background: The American Association for the Advancement of Science (AAAS), AMS, Ecological Society of America, Geological Society of America, and the Pew Center on Global Climate Change co-hosted the seminars with the Senate Energy and Natural Resources Committee, Senate Commerce, Science, and Transportation Committee, and the House Science and Technology Committee. In addition to Solomon, featured panelists included former Senator Tim Wirth, Peter Gleick (president and co-founder of the Pacific Institute for Studies in Development, Environment, and Security), and Ted Parson (Professor of Law and of Natural Resources & Environment at the University of Michigan). Dr. Solomon's presentation drew from her recent work as co-chair of Working Group I of the Intergovernmental Panel on Climate Change.
Significance: Solomon's participation in these seminars contributes to NOAA's efforts to provide policy-relevant scientific information to support national and international decisions on climate.
More information: http://www.aaas.org/spp/cstc/pne/events/climate09briefing.shtml
Deb Wilson honored with OAR Employee of the Year Award
entered on 12th Dec, 2008 01:04:06 PM MSTDebra R. Wilson, Administrative Officer of the ESRL Chemical Sciences Division, was the recipient of OAR's Employee of the Year Award. She was presented with the award by Dr. Spinrad at a ceremony in Silver Spring, MD, on December 11.
Deb was awarded in two categories, Personal/Professional Excellence and Administrative/Technical Support. The citation for Deb's award reads: For indispensable contributions as Administrative Officer that have been vital to the success of the Chemical Sciences Division.
Background: As the Administrative Officer, first for the NOAA Aeronomy Laboratory and later the Chemical Sciences Division of the Earth System Research Laboratory, Deb has, for 25 years, been the key focal point for all those who are/were members of those organizations. In this capacity, she has made a sustained and cumulative contribution that is absolutely vital to the functioning and success of the Chemical Sciences Division. The year 2008 brought extraordinary demands related to a major reorganization of the CSD Division program areas and the execution of two major field missions in the Arctic. This exceptional performance in 2008 caps a career of excellence for Deb. Her achievements have enabled the Division to function at the highest scientific levels by ensuring that the day-to-day and longer-term operations would run smoothly.
20th Meeting of the Parties of the Montreal Protocol on the Ozone Layer
entered on 17th Nov, 2008 12:19:31 PM MSTThis week, CSD Director A.R. Ravishankara is at the 20th Meeting of the Parties to the Montreal Protocol (ozone layer) in Doha, Qatar, in his capacity as Cochair of the Protocol's "Scientific Assessment Panel."
At this meeting, discussion is expected on the topic of strengthening the agreements related to hydrochlorofluorocarbons (HCFCs), which are being used as substitutes for chlorofluorocarbons (CFCs). Though they are more ozone friendly than the CFCs they replace, the HCFCs still do destroy some stratospheric ozone.
Ravi will provide any scientific information that may be requested by the Parties for these discussions. In addition, he will give a presentation on the plans for the next scientific assessment of the ozone layer, which will be prepared during 2009 and 2010 per the terms of the Montreal Protocol.
Also attending the meeting is CSD scientist David Fahey, who will participate in discussions of ozone, climate, and the "world avoided" by the Montreal Protocol.
Background: The annual "Meeting of the Parties" is a decisionmaking meeting of the Protocol's ~190 signatory nations. They determine whether to take new measures to strengthen the Protocol's provisions regarding the protection of the ozone layer.
Significance: This activity underscores NOAA's role in providing scientific information that is input for decisions on global environmental issues. The work contributes to the Understanding Climate Processes capability of the Climate Goal's Climate Research and Modeling Program.
CCSP synthesis and assessment report on ozone depletion about to be released
entered on 6th Nov, 2008 02:43:27 PM MSTA new NOAA-led scientific assessment on the ozone layer, to be released November 13 as part of the series of Synthesis and Assessment reports coordinated by the U.S. Climate Change Science Program, gives a first-time emphasis on the U.S. perspective in the ozone depletion issue, and updates the status of the global ozone layer. The report also offers a glimpse into expectations for recovery of the ozone layer in a changing climate, as well as a first detailed look at U.S. role in emitting - and reducing the emissions of - the chemicals that deplete the ozone layer.
Dr. A.R. Ravishankara, Director of the Chemical Sciences Division of ESRL, was the lead for the report. The author team was composed of 16 scientists from NOAA, NASA, NSF, EPA, NRL/DOD, and USDA. NOAA authors were: John Daniel (CSD/ESRL); David Fahey (CSD/ESRL); Steve Montzka (GMD/ESRL); and V. Ramaswamy (GFDL). They developed information for and about the U.S., and drew material from two recent international scientific assessment reports to which the U.S. contributed, to distill a U.S.-specific perspective on this global issue.
The report finds that U.S. production and use of ozone-depleting substances have been significant throughout the history of the ozone depletion issue, contributing about 25 percent of the global amount produced during the period from 1986 to 1994. But by adopting the 1987 international Montreal Protocol agreement to protect the ozone layer, the report finds that the U.S. has also contributed significantly to healing the ozone layer by reducing the production and use of ozone-depleting substances. The U.S. percentage of the global total production has fallen to 10% in recent years.
The numbers reflect a decline of 97-98% in the U.S. production of the ozone-damaging chemicals since the late 1980s. U.S. actions have aided international efforts to achieve a recovery of the ozone layer, which is expected to occur about mid-century for most regions of the globe. Ozone depletion is not worsening, and in some regions the ozone layer is now showing early signs of recovery.
As the CCSP 2.4 report notes, without the Montreal Protocol, the levels of ozone-depleting substances in the "world we avoided" would likely have been 50 percent larger in 2010 than currently predicted.
Background: The ozone layer, which surrounds the globe about 10-15 miles above the surface, protects living things from the Sun's harmful ultraviolet rays. Chlorofluorocarbons (CFCs) used in refrigeration and air conditioning, along with other manmade substances, deplete stratospheric ozone. Above Antarctica, the extreme losses occurring each spring lead to an "ozone hole" above that continent. The ozone layer is expected to recover by mid-to-late this century, largely because of the actions taken by the international community to limit ozone-depleting substances such as CFCs. The 1987 Montreal Protocol and its subsequent amendments established limits and eventual phase-outs for production and consumption of several ozone-depleting substances.
Significance: This report provides a U.S. perspective on the global issue of stratospheric ozone depletion and gives decision-support scientific information on the topic. The work was completed as part of NOAA's Climate Goal-Climate Research and Modeling Program.