Earth Sciences

Five environmental groups are alleging that NASA could be about to break the commitments it made in a 2010 agreement to clean up all the detectable contamination at its former Santa Susana Field Lab (SSFL) rocket testing site in the Simi Hills of California.

They claim that NASA may be laying the groundwork for a breach by falsely claiming that commenters on its draft Environmental Impact Study (EIS) on the cleanup were evenly divided on whether NASA should live up to its obligations in the cleanup agreements. When pressed by environmental groups to provide actual data to backup such a claim, they say NASA refused, and one of the groups, Consumer Watchdog, submitted a Freedom of Information Act request, obtaining all submitted comments.

The extreme cold weather observed across Europe and the east coast of the US in recent winters is due to to natural, long-term variations in sea surface temperatures, according to a new study published in Environmental Research Letters.

The researchers from University of California Irvine show that the Atlantic Multidecadal Oscillation (AMO) phenomenon — a natural pattern of variation in North Atlantic sea surface temperatures that switches between a positive and negative phase every 60-70 years — can affect an atmospheric circulation pattern, known as the North Atlantic Oscillation (NAO), that influences the temperature and precipitation over the Northern Hemisphere in winter.

When Rachel Carson's "Silent Spring" was taking the country by storm 50 years ago, it was a puzzle to scientists and farmers who did not see the cultural future looming in front of them. Scientists dismissed it as anecdotal evidence while farmers recognized that if you don't use a pesticide according to instructions, bad things happen. Both knew that without pesticides, yields would be devastated.

The deepest areas of the Baltic Sea have always had a low oxygen content. The inflow of fresh water is actually limited by low thresholds at the entrance to the Baltic Sea.

At the same time, there is a relatively fresh layer above the denser and saltier water in the deep layer of the sea.

This results in an effective stratification of the water column, which prevents the mixing of water masses necessary to transfer oxygen to the water at the bottom.

Increasing heat is estimated to extend dry conditions to far more farmland and cities by the end of the century, according to a new paper.

Much of the concern about future drought under a global warming scenario has focused on rainfall projections but higher evaporation rates may also play an important role as warmer temperatures wring more moisture from the soil, even in some places where rainfall is forecasted to increase, say the authors, who use the latest computer simulations to model the effects of both changing rainfall and evaporation rates on future drought in the journal Climate Dynamics.

Consuming foods grown in urban gardens has become a big fad, and those foods might even offer health benefits, unless a lack of knowledge about the soil used for planting poses a health threat to both consumers and gardeners. 

A new paper the Johns Hopkins Center for a Livable Future (CLF), researchers identifies a range of factors and challenges related to the perceived risk of soil contamination among urban community gardeners and found a need for clear and concise information on how best to prevent and manage soil contamination. 

Greenhouse gas emissions from food production may threaten the UN climate target of limiting global warming to 2 degrees Celsius, according to a paper from Chalmers University of Technology, Sweden. What is the data? No data needed.

The largest earthquakes occur where oceanic plates move beneath continents. Obviously, water trapped in the boundary between both plates has a dominant influence on the earthquake rupture process.

Writing in
Nature Geoscience (28.03.2014), a group of scientists from the GFZ German Research Centre for Geosciences and from Liverpool University analyzed the Chile earthquake of February, 27th, 2010 and found that the water pressure in the pores of the rocks making up the plate boundary zone was key. 

Ammonia pollution from agricultural sources poses larger health costs than previously estimated, according to a numerical model by Harvard University researchers Fabien Paulot and Daniel Jacob, who estimated chemical reactions in the atmosphere to better represent how ammonia interacts in the atmosphere to form harmful particulate matter. The improved simulation helped the scientists narrow in on the estimated health costs from air pollution associated with food produced for export – a growing sector of agriculture and a source of trade surplus.

"The 'cost' is an economic concept to measure how much people are willing to pay to avoid a risk," Paulot said. "This is used to quantify the cost for society but also to evaluate the benefits of mitigation."