A new report investigates the causes of extreme weather and climate events that occurred around the world in 2013, finding evidence for both human and natural influences.

In coordination with the National Ocean Council, the Department of State is requesting expert reviewers for the draft United Nations World Ocean Assessment (WOA). The WOA assesses the ocean's role in the Earth system, food security and food safety, human activities, and biological diversity.

According to the UN’s World Meteorological Organization (WMO), a surge in carbon dioxide levels drove the amount of greenhouse gases in the atmosphere to a record high in 2013. Greenhouse gas levels rose more between 2012 and 2013 than at any time in the last 30 years.

New NASA research shows that Earth's atmosphere contains an unexpectedly large amount of carbon tetrachloride (CC14), an ozone -depleting chemical that was banned worldwide decades ago. According to the study, global emissions of CCl4 average 39 kilotons per year—approximately 30 percent of peak emissions prior to its banning.