Journal of Geophysical Research: Atmospheres

Cover image for Vol. 120 Issue 3

Impact Factor: 3.44

ISI Journal Citation Reports © Ranking: 2013: 24/173 (Geosciences Multidisciplinary)

Online ISSN: 2169-8996

Associated Title(s): Journal of Geophysical Research

Editors' Highlights

A database of African precipitation from 1983 onward (22 September 2014)
Satellite infrared observations are used to reconstruct African precipitation records for the past 30 years in an attempt to infer rainfall variability... [more]

Modeling waves in the atmosphere (6 August 2014)
How can a complex atmospheric process be simplified for a model?... [more]

History of storm surge in Florida strongly underestimated (21 July 2014)
The observational hurricane record for northwestern Florida is just 160 years long, yet hurricane activity is known to vary strongly over thousands of years... [more]

Improved measurements of atmospheric nitrous oxide (17 July 2014)
One of the main greenhouse gases, nitrous oxide (N2O), is known for its degrading effect on the Earth’s ozone layer. The gas is created both naturally, by microbial activity on land and in the oceans, and emitted by human-made processes, through fertilization or burning fossil fuels... [more]

Precooled aerosols are better raindrop nuclei (8 July 2014)
Cooling inorganic and organic aqueous solutions makes the particles into more robust seeds of clouds... [more]

New measurement of longwave irradiance (18 June 2014)
Researchers employ two types of independent instruments to obtain the most accurate measurements of longwave irradiance yet... [more]

Black carbon reductions in the Arctic tied to declining emissions (18 June 2014)
Black carbon, or soot, is now considered to be the second most potent driver of anthropogenic climate change, its effect on global temperatures trailing only that of carbon dioxide. Yet, where carbon dioxide emissions spread broadly across the planet, black carbon's effects are far more localized... [more]

Colorado hydrocarbon leakage rates much higher than reported (3 June 2014)
Airborne measurements put methane emissions from Colorado's Denver-Julesburg Basin at 12 to 26 tons per hour... [more]

Large volcanic eruptions cause drought in eastern China (3 June 2014)
In most cases, the annual East Asian Monsoon brings heavy rains and widespread flooding to southeast China and drought conditions to the northeast. At various points throughout history, however, large volcanic eruptions have upset the regular behavior of the monsoon... [more]

Cloud variations in current climate as a guide to climate changes (27 May 2014)
Different types of clouds will have different effects on climate in a warming world... [more]

Models of ozone changes do not agree with real measurements (13 May 2014)
Ozone (O3), an important component of the Earth’s atmosphere that is created by both natural and man-made processes, is a greenhouse gas, contributing to climate warming. Modeling the changes in concentrations of greenhouse gases, including O3, helps scientists project the effects of these gases in the future... [more]

Examining the causes of a devastating debris flow (2 April 2014)
Storm-triggered landslides cause loss of life, property damage, and landscape alterations. For instance, the remnants of Hurricane Camille in 1969 caused 109 deaths in central Virginia... [more]

New technique improves how scientists map lightning flashes (27 March 2014)
Lightning interferometers are instruments that make two-dimensional images of individual lightning discharges inside thunderstorms... [more]

Project provides new look at Saharan low-level jet streams (21 March 2014)
Hot, dusty Saharan winds are known to influence atmospheric processes in the greater Atlantic region, but the desert’s harsh environment makes meteorological observations of weather patterns originating in the Sahara nearly impossible... [more]

Updated global dataset tracks sea ice from 1850 to 2007 (19 March 2014)
For more than a century and a half, scientists, sailors, pilots, and others have collected measurements of everything from sea ice extent to temperature to atmospheric pressure, using a range of procedures, tools, and techniques... [more]

Identifying biases in satellite temperature and humidity records (18 March 2014)
NASA's Aqua satellite has been in orbit for more than a decade, and current projections expect it to hold out until the early 2020s. The satellite's long lifetime of continuous operation has made its observations particularly valuable for testing climate models... [more]

Peering into the microphysics of the Madden-Julian Oscillation (14 March 2014)
The onset of the active phase of the Madden-Julian Oscillation (MJO) is marked by the formation of a region of deep convection and enhanced precipitation over the Indian Ocean... [more]

Assessing model representations of stratospheric equatorial waves (7 March 2014)
From their formation in the tropical troposphere, some westward-propagating Rossby-gravity waves and eastward Kelvin waves can travel up through the atmosphere... [more]

Seeding cirrus clouds could drive global net cooling (1 March 2014)
Cirrus clouds—thin, wispy streamers that form in the upper troposphere when ice crystals nucleate around small dust or metallic particles... [more]

Texas refinery air pollution emissions are being severely underestimated (27 February 2014)
The Houston-Galveston-Brazoria region of southeastern Texas is home to heavy industrial investment in oil refining and petrochemical production. Pollutants coming off the factories and refineries have repeatedly caused the region to fail both national and state-level tests for air quality and ground-level ozone... [more]

California's ammonia emissions have been drastically underestimated (27 February 2014)
In California, Los Angeles and the Central Valley often have atmospheric concentrations of particulate matter that exceed the Environmental Protection Agency's health guidelines... [more]

Atmospheric ducts can transport sound in two directions (5 February 2014)
When conditions are right, temperature gradients and fast jets of wind can help to establish atmospheric ducts—pathways in the atmosphere that promote the propagation of low-frequency acoustic waves (infrasound)—across long distances... [more]

Model describes stratospheric condensation nuclei layer (31 January 2014)
Aerosol particles in the stratosphere, including the small particles known as condensation nuclei, affect atmospheric chemistry as well as how the atmosphere absorbs and scatters sunlight, making them a key component in Earth’s climate... [more]

Observing trends in total ozone and extreme ozone events (31 January 2014)
The ozone layer in the stratosphere has been recovering since the 1989 Montreal Protocol banned reduced the use of ozone-destroying chlorofluorocarbons. Fitzka et al. observed trends in total ozone levels and the vertical distribution of ozone... [more]

Vigorous vent lightning observed during Eyjafjallajökull eruption (23 January 2014)
Volcanoes do more than spew rock and magma—they also produce electrical discharges. Various mechanisms, including high-energy silicate fracturing and boiling of water upon contact with magma, can produce electrical sparks near the vent of a volcano... [more]

Measuring the effect of water vapor on climate warming (22 November 2013)
Water vapor is a potent greenhouse gas. In the atmosphere, the concentration of water vapor increases with the temperature, setting up a powerful positive feedback loop. This water vapor feedback is the strongest known positive feedback... [more]

Assessing new remote sensing aerosol detection algorithms (21 November 2013)
Atmospheric aerosols affect the weather and climate by changing cloud formation and the energy balance and, depending on their type and concentration, can negatively affect air quality. Important atmospheric aerosols include dust, ash, volcanic sulfate aerosols.... [more]

Anthropogenic aerosols increasing over India (31 October 2013)
Aerosol particles in the Earth’s atmosphere scatter and absorb light differently at different wavelengths, thereby affecting the amount of incoming sunlight that reaches the planet’s surface and the amount of heat that escapes, potentially altering the planet’s climate.... [more]

Using new satellite data would improve hurricane forecasts (28 October 2013)
To track and forecast the development of dangerous tropical cyclones, the National Weather Service’s National Centers for Environmental Prediction uses a model known as the Hurricane Weather Research and Forecasting (HWRF) system. HWRF is an operational model... [more]

Global top-down estimate of black carbon emissions (23 October 2013)
Black carbon, emitted during burning of fossil fuels, burning of biofuels, and other combustion, is an air pollutant and a major contributor to global climate change. Global-scale estimates of black carbon emissions are uncertain... [more]

Measuring global sulfur dioxide emissions with satellite sensors (16 October 2013)
Atmospheric sulfur dioxide affects the weather by enhancing cloud formation, and long-term shifts in emissions can change the climate by increasing the planetary albedo. Sulfur dioxide emissions are the basis for acid rain, and the gas itself can cause respiratory problems.... [more]

Comparing climate impact of different geoengineering methods (11 October 2013)
If efforts to control greenhouse gas emissions do not succeed in combating global warming, some scientists and policy makers may consider geoengineering the climate, even though this could be a risky strategy with potential drawbacks. One geoengineering.... [more]

Evaluating solutions to the faint young Sun problem (19 September 2013)
During the Archean eon, between about 3.8 billion years ago and 2.5 billion years ago, the Sun was about 20-25% fainter than it is today. With less sunlight to warm the Earth, the oceans should have been frozen over, but geological evidence suggests that.... [more]

Sudden geoengineering termination could cause a huge warming spike (16 September 2013)
Atmospheric concentrations of greenhouse gases are climbing, a trend that shows little sign of abating. This reality has prompted some scientists to very seriously consider the prospects of geoengineering. In a new modeling study looking at the consequences of geoengineering... [more]

Statistically linking extreme precipitation to global warming (9 September 2013)
Tree ring records are often used as a proxy for past climate. Trees form a new growth ring each year, and ring widths are related to temperature and other conditions at cold sites. Some recent studies have noted that tree ring width chronologies and resulting climate... [more]

Tree ring records not distorted by missing rings (29 August 2013)
Tree ring records are often used as a proxy for past climate. Trees form a new growth ring each year, and ring widths are related to temperature and other conditions at cold sites. Some recent studies have noted that tree ring width chronologies and resulting climate... [more]

How tropical humidity self-organizes into moist and dry regions (20 August 2013)
Numerical simulations have shown that the moisture in the tropical troposphere has a tendency to spontaneously aggregate, forming separate wet and dry regions. To learn more about how this self-organization occurs, Craig and Mack introduced a simple equation... [more]

Updated ice core record captures Industrial Era carbon variability (15 August 2013)
In 1999, researchers published data from ice cores collected at Law Dome, a research site in East Antarctica. These data are distinguished by their high time resolution, and by their overlap with modern measurements, providing one of the most important records of how the atmosphere's chemical composition... [more]

Identifying the chemical composition of “brown carbon” in the atmosphere (8 June 2013)
Aerosol particles in the atmosphere can either absorb or scatter incoming solar radiation, thus either heating or cooling the atmosphere. One of the most studied types of aerosols that absorb radiation is black carbon (also called soot), which comes from incomplete combustion... [more]

Assessing black carbon’s effects on climate (6 June 2013)
Black carbon aerosol, commonly known as soot, plays an important role in Earth’s climate system by absorbing solar radiation, affecting cloud process, and influencing melting of snow and ice. In fact, after carbon dioxide, black carbon is the second most important... [more]

Causality of deep convection from a cloud-resolving model (23 May 2013)
Understanding deep convection and clouds is among the most important goals of tropical weather and climate dynamics. Deep convection, the vertical transport of buoyant air through the depths of the atmosphere, controls cloud formation and precipitation rates... [more]

Southern California ozone pollution declining and changing in recent decades (9 May 2013)
Many studies have documented the decline in ozone pollution and its precursors in the Los Angeles air basin over the past several decades. Now Pollack et al. have analyzed new data from research aircraft, along with archived data from roadside monitors and ground-based... [more]

Can West African monsoon rainfall be predicted on decadal time scales? (6 May 2013)
The economies in much of West Africa are based on agriculture, which is strongly affected by rainfall variability. Thus, predictions of variations in West African monsoon rainfall could be valuable to people in those regions.... [more]

Uneven warming shifts equatorial rain band, midlatitude westerlies (4 May 2013)
In a band near the equator, southward Northern Hemisphere winds and northward Southern Hemisphere winds come together to form the Intertropical Convergence Zone (ITCZ). In the ITCZ the equatorward winds rise and cool, creating a region of high precipitation... [more]

How surface roughness affects the light-scattering properties of ice crystals (30 April 2013)
Many studies have focused on how the size and shape of ice crystals in clouds affect the clouds' light scattering properties, which are important in understanding the effects of clouds on weather and climate; these effects are one of the major sources of uncertainty... [more]

A fix to modeled biases in rainfall microphysical process rates (23 March 2013)

Much of the uncertainty in global climate models stems from issues involved in accurately representing cloud properties. The difficulty arises in parameterizing the small-scale physical interactions that turn water vapor to cloud to rain... [more]

Assessing the latest models' handling of climate extremes (27 February 2013)
In time for the slated September release by the Intergovernmental Panel on Climate Change of its fifth assessment report, Sillmann et al. conducted an assessment of the latest generation of global climate models and historical reanalysis datasets. The authors... [more]

Photochemistry complicates source attribution of volatile organic compounds (28 December 2012)

Understanding the sources of air pollution is important in mitigation efforts. Commonly used models known as receptor models often do not take into account chemical reactions that may occur between the source of the emission and the site where measurements are taken... [more]

Regional Models Do Not Add Much Value to Climate Change Projections (27 October 2012)

Global general circulation models are the dominant tool in the effort to forecast the effects of climate change. Given their expansive scope, some simplifications need to be made when representing smaller-scale processes, such as the effects of regional topogr... [more]

Simple formulas calculate cloud droplet concentration (26 September 2012)

Droplets in clouds form on atmospheric aerosols known as cloud condensational nuclei. More than 90% of cloud droplets nucleate within a few tens of meters above the base of clouds, where the air is supersaturated. The microphysical processes of drop formation ... [more]

In California, 5 decades of decreasing emissions (14 September 2012)

Volatile organic compounds (VOCs), which are emitted by vehicles and are a leading source of air pollution, have been on the decline in Los Angeles, Calif., one of the densest and most poorly ventilated cities in the United States, a new study finds. Comparing... [more]

Comparing secondary organic aerosol formation in two U.S. cities (12 September 2012)

Secondary organic aerosols (SOAs) form from the oxidation of volatile organic compounds (VOCs) in the atmosphere, and the composition and abundance of SOAs affect their effects on air quality, human health, and the planetary radiation budget. To investigate ho... [more]

Uncertainties in atmospheric mixing affect warming predictions (23 August 2012)

Uncertainties in the rates of small-scale mixing of greenhouse gases in the upper troposphere–lower stratosphere, between about 10 and 20 kilometers above Earth's surface, may be affecting predictions of how warm the Earth's surface could get i... [more]

Hotter days and droughts to continue through the 21st century (10 August 2012)

As heat waves become more frequent, and droughts cause famines and drive up food prices, climate policies will need to account for changes in extremes in temperature and precipitation, as global mean temperatures continue to rise through the 21st ce... [more]

Sea salt particles react with organic acids in atmosphere (2 August 2012)

Sea salt (sodium chloride, NaCl) particles lofted into the atmosphere by the motion of waves affect atmospheric chemistry; they can undergo reactions with trace atmospheric gases and internal mixing with anthropogenic pollutants depositing on particle surface.... [more]

Comparison with observations shows cloud simulations improving (18 July 2012)

Climate projections, such as those used by the Intergovernmental Panel on Climate Change, rely on models that simulate physical properties that affect climate, including clouds and water vapor content. Clouds and water vapor are difficult to simulate in global... [more]

Atmospheric carbon dioxide drove climate change during longest interglacial (7 July 2012)

Known as the marine isotope stage 11 (MIS 11), the interglacial period centered around 400,000 years ago was the longest and possibly the warmest interglacial in the past 0.5 million years. Because the orbital configurations, atmospheric greenhouse gas concent... [more]

Tropospheric gas at potentially toxic levels in air (21 May 2012)

Forest fires and emission of air pollutants, which include fumes from vehicles running on diesel and slow burning of coal and charcoal, release isocyanic acid in the troposphere. In 2011, scientists first detected isocyanic acid in the ambient atmosphere at le... [more]

Reanalyses find rising humidity in the Arctic but miss fine details (16 May 2012)

Direct, reliable observations of atmospheric conditions stretch as far back as the midseventeenth century, with otherwise consistent records being punctuated by periodic updates in methods, practitioners, and observational equipment. To bridge these shifts in ... [more]

New corrections for skylight estimates (9 May 2012)

Skylight, also known as diffuse solar radiation, accounts for about 16% of the total solar radiation reaching the Earth's surface; the percentage varies depending on external factors, such as the angle of the Sun with respect to the zenith and the composi... [more]

Ross Ice Shelf air stream driven by polar vortex cyclone (8 May 2012)

The powerful air and ocean currents that flow in and above the Southern Ocean, circling in the Southern Hemisphere's high latitudes, form a barrier to mixing between Antarctica and the rest of the planet. Particularly during the austral winter, strong westerly... [more]

Measuring the human contribution to atmospheric carbon dioxide (19 April 2012)

Although it is well established that humans are responsible for the modern increase in atmospheric carbon dioxide concentrations, the precise emission rates of carbon dioxide and other environmentally important gases are less well known. Traditionally, the rep... [more]

Satellite tracks seasonal changes in atmospheric heavy water (22 March 2012)

Ascending through the upper troposphere and lower stratosphere, from 10 to 30 km altitude, the steadily decreasing temperature causes water vapor containing the hydrogen isotope deuterium—HDO or heavy water—to preferentially condense out of the air... [more]

Improving operational plume forecasts (6 March 2012)

Forecasting how plumes of particles, such as radioactive particles from a nuclear disaster, will be transported and dispersed in the atmosphere is an important but computationally challenging task. During the Fukushima nuclear disaster, operational plume forec... [more]

Land use changes contribute to climate extremes (25 February 2012)

Temperature extremes such as severe heat waves and cold spells are likely to occur more frequently in a warming climate as carbon dioxide (CO2) concentrations rise. But land use change, such as clearing forests for agriculture, also has a large impa... [more]

Efficiency of organic aerosols as cloud condensation nuclei (22 February 2012)

Secondary organic aerosols, aerosols produced through chemical reactions in the atmosphere from volatile compounds, affect climate directly by reflecting sunlight and by acting as cloud condensation nuclei, promoting cloud formation. The efficiency with which ... [more]

Statistical technique seeks to reduce climate uncertainty (21 February 2012)

Three measures of the climate system—climate sensitivity, vertical ocean diffusivity, and sulfate aerosol forcing—underpin the current understanding of the power of anthropogenic climate change. Climate sensitivity reflects the equilibrium temperat... [more]

Asian emissions contribute to air pollution in western United States (17 February 2012)

As Asian countries develop, they are emitting more ozone precursors that pollute surface level air. Many studies have documented this pollution being carried by air currents to the western United States. To learn more about the mechanisms that transport air po... [more]

Remote sensing of volcanic ash properties (28 January 2012)

Remote sensing is an important tool to track hazardous volcanic plumes, providing an overview of the ash cloud. Francis et al. (2012) describe a method of using infrared data from instruments onboard the Meteosat satellite to detect volcanic ash and der... [more]

Improving forecasts of volcanic ash concentrations (27 January 2012)

Volcanic ash can severely damage airplanes, and eruptions such as the 2010 Eyjafjallajokull eruption may result in major disruption to air travel. Improved forecasting of ash cloud locations and concentrations could benefit the aviation industry and reduce del... [more]

Effects of sea spray geoengineering (25 January 2012)

Anthropogenic climate warming is leading to consideration of options for geoengineering to offset rising carbon dioxide levels. One potential technique involves injecting artificial sea spray into the atmosphere. The sea salt particles would affect Earth's rad... [more]

When will Antarctic ozone begin to recover? (18 November 2011)

Emissions of ozone-depleting substances have declined over recent decades, but it takes time for the ozone layer to recover. Regular measurements of ozone levels above the South Pole now stretch back 25 years. Hassler et al. (2011) analyzed this recorde... [more]

Glyoxal contribution to aerosols over Los Angeles (28 October 2011)

Laboratory and field studies have indicated that glyoxal (chemical formula OCHCHO), an atmospheric oxidation product of isoprene and aromatic compounds, may contribute to secondary organic aerosols in the atmosphere, which can block sunlight and affect atmosph... [more]

Climate model's historical accuracy no guarantee of future success (10 September 2011)

To validate and rank the abilities of complex general circulation models (GCMs), emphasis has been placed on ensuring that they accurately reproduce the global climate of the past century. But because multiple paths can be taken to produce a given result, a mo... [more]

UV solar irradiance was low during recent solar minimum (16 August 2011)

Solar irradiance, which varies with the 11-year solar cycle and on longer time scales, can affect temperature and winds in the atmosphere, influencing Earth's climate. As the Sun currently wakes up from a period of low sunspot activity, researchers want to kno... [more]

Surge in North Atlantic hurricanes due to better detectors, not climate change (26 May 2011)

A spate of research has indicated there may be a link between climate change and the prevalence of North Atlantic tropical cyclones. Upon closer inspection, however, researchers have noted that the prominent upswing in tropical cyclone detections beginning in ... [more]

Simulating observations of solar irradiance (24 May 2011)

Rising concentrations of carbon dioxide and other greenhouse gases in the atmosphere change how much solar radiation is reflected back into space. A proposed NASA mission, Climate Absolute Radiance and Refractivity Observatory (CLARREO), would make benchmark m... [more]

Improving global estimates of land surface properties (11 May 2011)

Large models often rely on numerical simplifications of complex or small-scale processes, usually because the underlying mechanisms are not well understood or direct observations are unavailable. The values for these parameterizations can be tuned to fit obser... [more]

Tropical atmospheric circulation and precipitation changing (7 May 2011)

As Earth's climate has warmed over the past several decades, atmospheric and hydrological cycle changes are being observed globally and regionally. For instance, Zhou et al. (2011) analyzed trends in the hydrological cycle in the tropics over the past 2... [more]

Building an atlas of Arctic climate dynamics (12 April 2011)

The oceans and atmosphere act as a giant heat mixer. However, they do not spread energy evenly across the planet—the overall effect is a net poleward transfer of energy. While it is known that this energy is predominantly moved by traveling air packets a... [more]

Understanding the behavior of mercury in the cryosphere (24 March 2011)

Anthropogenic emission of mercury is increasing, especially in Asia. Mercury in the atmosphere can be deposited into the cryosphere, regions covered by snow and ice. Some of the mercury deposited into the cryosphere is emitted back to the atmosphere, and some ... [more]

Ash from huge Australian bushfires in 2009 circled the globe (19 March 2011)

On 7 February 2009, record high temperatures, low rainfall and humidity, and fast blowing winds caused sparks in the bush near the Australian city of Melbourne to ignite much of the southeastern region of the state of Victoria. In just a few days, more than 45... [more]

Atmospheric aerosols and climate over East Asia (17 February 2011)

As the most heavily populated and fastest-developing region of the world, East Asia is a major source of anthropogenic aerosols, which can affect air quality and climate. In addition, the arid regions of its interior are a significant source of dust in the atm... [more]

Water vapor trends over Boulder, Colorado (26 January 2011)

Water vapor in the atmosphere is responsible for a significant portion of the greenhouse effect, and even small changes in the upper troposphere or lower stratosphere can have a large effect on climate. A new analysis of balloon-borne water vapor measurements ... [more]

Soil temperature trends in Canada (21 January 2011)

Global warming is increasingly becoming a concern for society. Most reported warming trends are based on measured increases in air temperatures. However, trends in soil temperatures, also an important indicator of climate change, are less often reported. Qi... [more]

Comparing different land surface heat flux estimates (20 January 2011)

Land surface heat fluxes are an important component of Earth's energy and water cycle, and quantifying these fluxes can help scientists better understand climate change. These heat fluxes are affected by factors such as cloud cover, precipitation, surface radi... [more]

Three-dimensional ash cloud observations could help keep planes in the air (21 December 2010)

In the spring of 2010 the Icelandic volcano Eyjafjallajökull erupted, sending a towering column of ash floating above the North Atlantic Ocean. The ash cloud shut down air traffic over much of Europe, significantly affecting the European economy. Although... [more]