Three of the last eight months this year were the hottest on record, according to the latest federal climate data, which found that last month was the warmest August worldwide. Average temperatures in May and June were similarly record-breaking, and this July was the fourth-hottest since scientists began keeping track 130 years ago.

Temperatures in August exceeded the 1951-1990 baseline average by 0.70 degrees Celsius, the NASA Goddard Institute for Space Studies said this week. While that makes it the top-ranked August, scientists said the difference is statistically tiny compared with the Augusts of 2011, 2008, 2006 and 2003, reported.

August 2014 Temperature Change in August surface temperatures from 1880 to 2014, in degrees Celsius. Photo: NASA Goddard Institute for Space Studies

Gavin Schmidt, a climatologist and climate modeler at the Goddard institute, said the string of record-warm months is only a small part of the larger dataset that points toward a long-term trend of global warming, the Huffington Post reported.

Although monthly and yearly temperatures fluctuate, Earth’s overall average temperature is rising as heat-trapping greenhouse gas emissions build up in the atmosphere -- the bulk of which come from human activities like burning fossil fuels and clearing rain forests. A recent report found that carbon dioxide levels increased more between 2012 and 2013 than during any other year in the past three decades.