The Steel Recycling Institute (SRI), a business unit of the American Iron and Steel Institute, released a peer-reviewed study that examines the overall environmental impact of vehicle lightweighting using advanced high-strength steel (AHSS) compared with aluminum. The study, “Life Cycle Greenhouse Gas and Energy Study of Automotive Lightweighting,” found that... Read more →

Global Carbon Project reports global CO2 emissions suddenly on the rise after 3-year hiatus; need for reducing uncertainties

Global emissions of carbon dioxide from burning fossil fuels have risen again after a three year hiatus, according to new analysis from the Global Carbon Project (GCP). According to the GCP, global emissions from all human activities will reach 41 billion tonnes in 2017, following a projected 2% rise in... Read more →

A collaboration led by researchers at Leiden University in The Netherlands has launched a Europe-wide citizen campaign—iSPEX-EU 2015—to use a smartphone add-on and app to measure atmospheric aerosols (tiny particles), resulting in a broad-based data set with high spatio-temporal resolution. Atmospheric aerosols play an important but as-yet poorly understood role... Read more →

The UN Intergovernmental Panel on Climate Change (IPCC) released the Synthesis Report that distills and integrates the findings of the full IPCC Fifth Assessment Report (AR5) released over the past 13 months. The report expresses with greater certainty than in previous assessments that emissions of greenhouse gases and other anthropogenic... Read more →

The ACME Project Roadmap, showing the relative sequencing of major simulation campaigns, model version development, and machine deployment. Click to enlarge. Eight national laboratories—Lawrence Livermore, Argonne, Brookhaven, Lawrence Berkeley, Los Alamos, Oak Ridge, Pacific Northwest and Sandia—are combining forces with the National Center for Atmospheric Research, four academic institutions and... Read more →

Study finds rising temperatures increase risk of unhealthy ozone levels absent sharp cuts in precursors

Ozone pollution across the continental United States will become far more difficult to keep in check as temperatures rise, according to new work led by the National Center for Atmospheric Research (NCAR). The study shows that Americans face the risk of a 70% increase in unhealthy summertime ozone levels by... Read more →

Decomposition of the decadal change in total global CO2 emissions from fossil fuel combustion by four driving factors; population, income (GDP) per capita, energy intensity of GDP and carbon intensity of energy. WG III Summary for Policymakers. Click to enlarge. The UN Intergovernmental Panel on Climate Change (IPCC) released a... Read more →

Schematic overview of the primary black-carbon emission sources and the processes that control the distribution of black carbon in the atmosphere and determine its role in the climate system. Source: Bond et al. Click to enlarge. Black carbon (BC) is the second largest man-made contributor to global warming and its... Read more →

World Bank report examines likely impacts and risks associated with a 4 °C global warming within this century

A new report commissioned by the World Bank, and prepared by the Potsdam Institute for Climate Impact Research (PIK) and Climate Analytics, provides a snapshot of recent scientific literature and new analyses of likely impacts and risks that would be associated with a 4 °C global warming within this century.... Read more →

PwC analysis finds a need for global carbon intensity to drop an average of 5.1% per year through 2050. Click to enlarge. The low annual rate of global reduction of carbon emissions per unit of GDP needed to limit global warming to 2 °C—based on the probability assessments of the... Read more →

This diagram illustrates the effect of phase on the chemical reactivity of adipic acid, a common atmospheric particle. (Image courtesy of Kuwata Mikinori.) Click to enlarge. Atmospheric chemists at the Harvard School of Engineering and Applied Sciences (SEAS) have found that the phase of secondary organic materials (SOM) in the... Read more →

A new generation of climate models will be needed to address a wide spectrum of climate information needs. A national strategy consisting of four key unifying elements and several other recommendations can help to achieve this vision. Source: NRC. Click to enlarge. Climate models will need to evolve substantially to... Read more →

Shipping-induced global temperature change in 2050 using different parameterizations of Indirect Aerosol Effect (IAE). Credit: ACS, Lund et al. Click to enlarge. A recent study by an international team calculated that shipping causes a net cooling of climate across all parametrizations of the indirect aerosol effect (IAE) and scenarios throughout... Read more →

Projected sea-level rise off California, Oregon, and Washington for 2030 (blue), 2050 (green), and 2100 (pink), relative to 2000, as a function of latitude. Solid lines are the projections, and shaded areas are the ranges. Ranges overlap, as indicated by the brown shading (low end of 2100 range and high... Read more →

Interpolated surfaces showing the change in mean annual temperature across Alaska for three different time series: 1949−2009, 1949−1976, and 1977−2009. Red colors represent a temperature increase, blue indicates a decrease, and beige indicates no change. Credit: ACS, Stevenson et al. Click to enlarge. Demonstrating that the use of different time... Read more →

Projected changes in summer mean usable capacity of power plants in the US and Europe for the SRES A2 emissions scenario for the 2040s (2031–2060) relative to the control period (1971–2000). Source: van Vliet et al. Click to enlarge. A study published in Nature Climate Change suggests that thermoelectric power... Read more →

Representation of SOA formation and growth based on the experimental observations. Credit: Perraud et al. Click to enlarge. A new study led by a team from the University of California, Irvine is providing important new insight into the mechanisms by which secondary organic aerosol (SOA) particles form and grow. The... Read more →

Criegee intermediates (CIs) play a central role in the formation of numerous atmospheric compounds. Welz et al. succeeded in isolating the simplest CI and reported direct kinetic measurements of its reactions with water, NO, NO2, and SO2. Credit: Marston (2012), Photo credit: Daniel Stein/ to enlarge. Molecules called Criegee intermediates—carbonyl... Read more →

Study using paleoclimate data suggests climate sensitivity to CO2 doubling may be less severe than projected

A new study, funded by the National Science Foundation’s Paleoclimate Program and published online this week in the journal Science, suggests that the rate of global warming from doubling of atmospheric carbon dioxide from pre-industrial times may be less than the most extreme estimates of some previous studies and may... Read more →

MIT researchers improve upon methods to model urban air pollution

Researchers at MIT have developed a new detailed air-quality model to simulate the effects of physical, chemical, and meteorological processing of highly reactive trace species in urban areas. The new metamodel is capable of efficiently simulating the urban concentration, surface deposition, and net export flux of these species that are... Read more →

New Bayesian Approach Addressing Shared Biases Across Models Suggests That Stabilizing CO2 Concentrations at Current Levels Leaves 10% Chance of Exceeding 2°C Target

According to an analysis based on a new hierarchical Bayes framework developed by Derek Lemoine at UC Berkeley that addresses shared biases across models, stabilizing atmospheric concentration of CO2 at current levels leaves a 10% chance of exceeding the 2°C target increase relative to pre-industrial level that most policymakers have... Read more →

Evolution of the carbon dioxide emissions calculated by the model (left) and the temporal development of the global mean annual temperature (right). In order to achieve the long-term stabilization of the atmospheric carbon dioxide concentration, fossil carbon dioxide emissions must be reduced to around zero by the end of the... Read more →

Schematic diagram of the trade-offs between the implications for regional air quality and global climate change of new policies for management of the atmosphere. The gray ellipse approximately represents the direction of current trends in the US. Source: NOAA. Click to enlarge. The California Air Resources Board (ARB) and the... Read more →

Top left. Bubble plumes (probably dominated by CH4) rising from the seafloor registered by geophysical instrumentation. Top right. seismic image showing gas charged sediments and gas release from the bottom. Bottom left. Positions of oceanographic stations with bathymetry lines. Bottom right. Fluxes of CH4 venting to the atmosphere over the... Read more →

Decadal warming rates arising from (i) greenhouse gases and aerosols alone (black); (ii) that obtained including the stratospheric water decline after 2000 (red); and (iii) including both the stratospheric water vapor decline after 2000 and the increase in the 1980s and 1990s (cyan). Credit: Solomon et al., Science. Click to... Read more →

by Jack Rosebro Total anthropogenic emissions (thick solid line) and amount of total emissions (46%) remaining in the atmosphere as the airborne fraction (thick dashed line). Thinner lines represent observed atmospheric CO2 increase derived from direct measurements, taking the average of Mauna Loa (Hawaii) and the South Pole (thin solid... Read more →

Organic aerosols from different sources undergo chemical processing and mix with each other as well as with inorganic aerosols. This leads to a convergence in their chemical and optical properties and in their ability to nucleate cloud droplets. Credit: M. O. Andreae Science 326, 1493-1494 (2009) Click to enlarge. Organic... Read more →

QUANTIFY Study Finds GHG Emissions from Global Transport Could Double Their Net Contribution to Warming by 2100

Transport emissions could double their current relative net contribution to global warming by 2100, according to a new study by researchers at the Oslo-based Centre for International Climate and Environment Research (CICERO) in Norway. The study’s results, presented in the journal Atmospheric Environment, are part of the EU-funded QUANTIFY (Quantifying... Read more →

The 100-year global warming potentials (GWPs) for methane, CO, and NOx (per Tg N) as given in the AR4 and in this study when including no aerosol response; the direct radiative effect of aerosol responses; and the direct+indirect radiative effects of aerosol responses. Source: Shindell at al. Click to enlarge.... Read more →

Schematic illustrating feedback pathways coupling terrestrial carbon and nitrogen cycles in the integrated model. Blue arrows show, in general, the processes represented in previous carbon-only land model components. Orange arrows show the additional processes represented in the coupled carbon-nitrogen land model, differentiated here between rapid internal cycling (solid arrows), and... Read more →

The total reductions of the three scenarios used in the PBL analysis. Source: PBL. Click to enlarge. The current proposals by developed countries on the table for the upcoming climate negotiations in Copenhagen to reduce greenhouse gas (GHG) emissions do not yet suffice to limit global warming to a rise... Read more →

Modeled yield of epoxides from the reaction of isoprene and OH. Grid cells where isoprene mixing ratio is lower than 50 pptv are not shown. Paulot et al. (2009). Click to enlarge. A team of researchers from the US, Denmark and New Zealand have discovered a process through which a... Read more →

Time series of annual mean values of cloud and climate quantities averaged over the NE Pacific. (A) COADS cloud data. (B) ISCCP cloud data. (C) COADS SST data. (D) Hadley Centre SLP data. Clement et al. (2009), Science. Click to enlarge. Low-level stratiform clouds—which play an important climatic role because... Read more →

Researchers Find that CO2 Forcing Alone Doesn’t Explain Magnitude of Ancient Global Warming Episode

By analyzing data from deep-sea sediment cores to study an ancient global warming episode (the Paleocene-Eocene Thermal Maximum, PETM), researchers found a less-than two-fold increase (70%) in atmospheric carbon dioxide levels corresponding to the 5–9 °C (9-16 °F) warming of the PETM. Based on current knowledge and models of the... Read more →

As areas with permafrost thaw and more old carbon is released, the carbon balance changes. Credit: Zina Deretsky, National Science Foundation. Click to enlarge. Permafrost thaw will make potentially significant contributions to atmospheric concentrations of carbon more rapidly that previously thought, according to a new study published in the 28... Read more →

The theme of the current issue of Nature is that the climate situation may be even worse than you think. Less than a quarter of the proven fossil fuel reserves can be burnt and emitted between now and 2050, if global warming is to be limited to two degrees Celsius... Read more →

New Study Shows that Sea Level Rise Resulting From Collapse of West Antarctic Ice Sheet Would be Non-Uniform; Some Regions to See Levels Much Higher Than Previously Predicted

Sea-level change in response to the collapse of the WAIS computed by using (A) a standard eustatic sea-level theory and (B) the new model. (C) shows the difference between predictions generated by using the two sea-level theories [(B) minus (A)]. Source: Mitrovica et al. (2009) Click to enlarge. A new... Read more →

Study Concludes That Climate Change Alone Could Erode US Improvements in Ground Level Ozone Events Resulting from Reduced Emissions

Differences in the average (June-August) MDA8-O3 mixing ratios (ppbv) in the surface layer (984-934 hPa) corresponding to (a) climate change under present emissions; (b) A2 emissions change under present climate; (c) climate change under A2 emissions; (d) B1 emissions change under present climate; and (e) climate change under B1 emissions).... Read more →

New Model for Global Atmospheric Circulation

Schematic representation of the proposed model of global atmospheric circulation. Red and blue arrows show the moist branch of the circulation corresponding to the additional mass transport on moist isentropes, with warm moist air moving toward the mid-latitudes at low levels, rising into the upper troposphere within the storm tracks,... Read more →