Since the 1990s, scientists and policymakers have proposed limiting Earth’s average global surface temperature to 2 degrees C above pre-industrial levels, thereby averting the most serious effects of global warming, such as severe droughts and coastal flooding. But until recently, they lacked a comprehensive estimate of the likely social and economic benefits — from lives saved to economies preserved — that would result from greenhouse gas emissions reduction policies designed to achieve the 2 C goal.

Now, a team of researchers from the MIT Joint Program on the Science and Policy of Global Change has published a study in Climatic Change that provides scenarios that climate scientists can use to estimate such benefits. The study projects greenhouse gas emissions levels and changes in precipitation, ocean acidity, sea level rise and other climate impacts throughout the 21st century resulting from different global greenhouse gas (GHG) mitigation scenarios. The scenarios include a business-as-usual future and one aimed at achieving significant GHG emission reductions limiting global warming since pre-industrial times to 2 C. Research groups convened by the U.S. Environmental Protection Agency have already begun using the MIT projections to evaluate the benefits of a 2 C emissions reduction scenario for agriculture, water, health, and other global concerns.

Particulate matter and NO2 air pollution are associated with increased risk of severe heart attacks despite being within European recommended levels, according to research presented at ESC Congress today by Dr Jean-Francois Argacha, a cardiologist at University Hospital Brussels (UZ Brussel-Vrije Universiteit Brussel), in Belgium.1

"Dramatic health consequences of air pollution were first described in Belgium in 1930 after the Meuse Valley fog," said Dr Argacha. "Nowadays, the World Health Organization (WHO) considers air pollution as one of the largest avoidable causes of mortality. Besides the pulmonary and carcinogenic effects of air pollution, exposition to air pollution has been associated with an increased risk in cardiovascular mortality."

As a raindrop falls through the atmosphere, it can attract tens to hundreds of tiny aerosol particles to its surface before hitting the ground. The process by which droplets and aerosols attract is coagulation, a natural phenomenon that can act to clear the air of pollutants like soot, sulfates, and organic particles. Atmospheric chemists at MIT have now determined just how effective rain is in cleaning the atmosphere. 

A University of Texas at El Paso (UTEP) study on children’s health has found that fourth and fifth graders who are exposed to toxic air pollutants at home are more likely to have lower GPAs.

At the end of November, governments will come together in Paris to hammer out agreements for a successor to the Kyoto Protocol. Under the KP, there are two greenhouse gas (GHG) emissions offsetting mechanisms: joint implementation (JI) and the Clean Development Mechanism (CDM).

JI allows countries with emissions-reduction commitments under the Kyoto Protocol to generate Emission Reduction Units (ERUs) from GHG reduction projects and transfer them to other countries. Almost 872 million ERUs had been issued under JI as of March 2015, about a third of all Kyoto offset credits. In a nutshell, JIs are carbon credits and include things like reforestation projects.

Everyday cosmetic and cleaning products contain huge quantities of plastic particles, which are released to the environment and could be harmful to marine life, according to a new study. Research at Plymouth University has shown almost 100,000 tiny ‘microbeads’ – each a fraction of a millimetre in diameter – could be released in every single application of certain products, such as facial scrubs.

New research by European and African scientists, including a team from the University of York, warns of the risks posed by the increasing air pollution over the cities of West Africa – amid fears it could have an impact on human health, meteorology and regional climate.

Once mercury is emitted into the atmosphere from the smokestacks of power plants, the pollutant has a complicated trajectory; even after it settles onto land and sinks into oceans, mercury can be re-emitted back into the atmosphere repeatedly. This so-called “grasshopper effect” keeps the highly toxic substance circulating as “legacy emissions” that, combined with new smokestack emissions, can extend the environmental effects of mercury for decades.

Now an international team led by MIT researchers has conducted a new analysis that provides more accurate estimates of sources of mercury emissions around the world. The analysis pairs measured air concentrations of mercury with a global simulation to calculate the fraction of mercury that is either re-emitted or that originates from power plants and other anthropogenic activities. The result of this work, researchers say, could improve estimates of mercury pollution, and help refine pollution-control strategies around the world.

The IPCC has over-estimated China's emissions since 2000 by 14%, almost 3 gigatonnes of carbon since 2000, while its energy consumption has been 10% higher than realised, writes Eliza Berlage. The country is far more carbon-efficient than we ever knew.

Although the Grand Canyon segment of the Colorado River features one of the most remote ecosystems in the United States, it is not immune to exposure from toxic chemicals such as mercury according to newly published research in Environmental Toxicology and Chemistry. The study, led by the U.S. Geological Survey, found that concentrations of mercury and selenium in Colorado River food webs of the Grand Canyon National Park, regularly exceeded risk thresholds for fish and wildlife.