May 2015 is the hottest May on record. In the United States, it is the wettest. Texas receives enough rainfall to cover the entire state in eight inches of water, leading to the worst flooding in the state's history.

BP agrees to pay $18.7 billion to settle claims filed after the 2010 Deepwater Horizon oil spill. It is the largest environmental settlement in U.S. history.

A Dutch court rules that the Netherlands' planned carbon-emissions reductions of 17 percent are insufficient and orders cuts of 25 percent over the next five years. 

Norway says it will divest its $900 billion sovereign wealth fund of companies that generate more than 30 percent of their revenues from coal. 

In India, a heat wave with temperatures approaching 120°F kills more than 2,500 people. A month later, scorching heat claims more than 1,000 lives in neighboring Pakistan. 

The U.S. Fish and Wildlife Service extends Endangered Species Act protection to all chimpanzees, effectively ending invasive research on those in captivity.

A ruptured pipeline sends more than 100,000 gallons of oil into the Pacific Ocean near Santa Barbara, California. 

Ecuador plans to auction off one-third of its Amazonian rainforest to Chinese oil companies. 

The Obama administration conditionally approves Shell's plans to drill for oil in the Chukchi Sea off Alaska. The government acknowledges that there is a 75 percent chance of one or more large spills during the life of the project.

The first completely wild condor to be born in California's Big Sur area in more than a century is treated for lead poisoning.

All new U.S. electric generation capacity in the month of April comes from wind and solar. 

CEOs from some of the largest oil companies ask the world's governments to put a price on carbon as they seek to reduce emissions. 

The EPA moves to regulate carbon emissions from commercial airplanes. 

More than 134,000 endangered saiga antelope—half of the entire population—die in a two-week period in May in Kazakhstan. 

The Department of the Interior calls for the mining of 10.2 billion tons of coal on public lands in the Powder River Basin in Montana and Wyoming. The carbon pollution from that coal will far surpass the savings from the EPA's Clean Power Plan. 

An EPA study confirms that fracking can pollute drinking water. 

Patriot Coal and four other coal companies file for bankruptcy, bringing to 42 the number of coal company bankruptcies in the past three years.

Polar bears are eating dolphins that have migrated to the Arctic in search of colder waters. 

 A prominent creationist in Alberta, Canada, discovers the fossil of a 60-million-year-old fish.