portion of a graph of atmospheric carbon dioxide over past glacial cycles and today
November 5, 2020

Fossil fuels are the only source of carbon dioxide large enough to raise atmospheric carbon dioxide amounts so high so quickly. 

A single bloom of Mountain avens in an alpine valley
October 29, 2020

Earth has warmed in the past due to changes in the Sun, volcanic eruptions, and naturally occurring increases in greenhouse gases. Our ability to understand and explain past changes is one reason we are confident that recent changes are due to humans. 

Cartoon of a rollercoaster whose hills and descents follow the outline of global surface temperatures over the past 10,000 years
January 23, 2014

Today's global warming is happening at a much faster rate today it did in the warm periods between ice ages over the last million years.

December 12, 2017

NOAA scientists have released the 2017 Arctic Report Card: the complete guide to climate conditions in the planet's Far North. 

June 17, 2015

Global warming is one symptom of the much larger problem of human-caused climate change.

September 17, 2014

Natural variability can explain much of Earth's average temperature variation since the end of the last ice age, but over the past century, global average temperature has risen from near the coldest to the warmest levels in the past 11,300 years.

June 24, 2020

Not a Mad Lib! Our blogger lays out some of the evidence for and against the notion that volcanic eruptions can trigger El Niño.