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. 

There can be no question that the epic story of our time is our struggle to endure against the threatening demons of our own creation. In that story, China must be the sleeping giant. As the story opens, the giant awakens, searching for a way to improve the livelihood of his people, inadvertently trampling on a number of the Earth’s delicate structures in doing so. Realizing this, a second awakening occurs. But can the giant change direction quickly enough, before too much harm is done?

The damage that re-directed the giant was the realization that fossil fuel emissions, particularly from coal-fired power plants, are pushing atmospheric carbon levels to dangerously high levels. China’s emissions have grown 7 percent annually — far faster than the rest of the world, which is growing at 2.8 percent. Now that we all realize that emissions have to start decreasing, fast, China has pledged to achieve peak emissions by 2030, after which its emissions will begin to decrease.

Prior to the advent of human-caused global warming in the 19th century, the surface layer of Earth's oceans had undergone 1,800 years of a steady cooling trend, according to a new study. During the latter half of this cooling period, the trend was most likely driven by large and frequent volcanic eruptions.

An international team of researchers reported these findings in the August 17, 2015 issue of the journal Nature Geoscience. The study also indicates that the coolest temperatures occurred during the Little Ice Age--a period that spanned the 16th through 18th centuries and was known for cooler average temperatures over land.

Nearly 2 million people throughout the Great Plains and California live above aquifer sites contaminated with natural uranium that is mobilized by human-contributed nitrate, according to a study from the University of Nebraska-Lincoln.

President Obama's plan to cut greenhouse gas emissions may look like a climate victory, writes Tim Kruger - but it's no such thing. It's feeble because the US can meet its targets by reducing emissions to 2030 more slowly than it has since 2000. And it's fragile as any future President can scrap it at will.

Climate change-denying Republicans hate this plan (of course), therefore all good climate realists see it as a triumph. But it is a tiny, tiny step in the right direction and climatically immaterial.

No doubt, you heard the good news. Barack Obama has announced the US is pushing through plans to reduce emissions of greenhouse gases. Rejoice! Rejoice! We've got this climate problem licked - hurrah!

As part of the Administration's Climate Action Plan – Strategy to Reduce Methane Emissions, the U.S. Environmental Protection Agency (EPA) issued two proposals to further reduce emissions of methane-rich gas from municipal solid waste (MSW) landfills. Under today’s proposals, new, modified and existing landfills would begin collecting and controlling landfill gas at emission levels nearly a third lower than current requirements. 

Methane is a potent greenhouse gas with a global warming potential more than 25 times that of carbon dioxide. Climate change threatens the health and welfare of current and future generations. Children, older adults, people with heart or lung disease and people living in poverty may be most at risk from the health impacts of climate change. In addition to methane, landfills also emit other pollutants, including the air toxics benzene, toluene, ethylbenzene and vinyl chloride. 

Approximately 31 percent of food produced in the U.S., or 133 billion pounds of food worth $162 billion, was wasted in 2011 according to the United States Department of Agriculture (USDA). Now, University of Missouri researchers have found that the type of food wasted has a significant impact on the environment. Although less meat is wasted (on average) compared to fruits and vegetables, the researchers found that significantly more energy is used in the production of meat compared to the production of vegetables. This wasted energy is usually in the form of resources that can have negative impacts on the surrounding environment, such as diesel fuel or fertilizer being released into the environment.

A report concludes that blooms of toxic cyanobacteria, or blue-green algae, are a poorly monitored and underappreciated risk to recreational and drinking water quality in the United States, and may increasingly pose a global health threat.