Data released last week by the National Oceanic and Atmospheric Administration (NOAA) shows that the string of monthly global heat records extended through February, when the average worldwide temperature was 2.18 degrees Fahrenheit above the 20th century average. The tenth straight record breaking month, February was the most above-normal month since meteorologists began tracking temperatures in 1880.
The nearly six-tenths of a degree margin by which it beat the old February record, set last year, had federal scientists describing temperatures as "staggering." That margin was confirmed by the National Aeronautical and Space Administration, which uses statistical techniques different than NOAA's, as well as a University of Alabama Huntsville team and the private Remote Sensing System team, which relies on measurements from satellites.
"Yes, of course El Niño has a hand in the February and other monthly temperatures records we've been observing, but not the only hand, not even the winning hand," Jessica Blunden of NOAA's National Center for Environmental Information told Mashable. "During the last big El Niño event of 97/98, temperatures departures from average were much lower compared with what we're seeing now with this comparable event, which shows us that general warming is occurring over time."
Many scientists say climate change is contributing to the recent high temperatures.
"We know that atmospheric CO2 (carbon dioxide) and other greenhouse gases are continuing to increase, so that's contributing to climate change and rising temperatures overall," said Heather Graven, a climate scientists at the Imperial College of London.
Another clue that rising greenhouse gases are contributing to the recent high temperatures is the location of the warmest-compared-to-average temperatures--the far northern latitudes, which are relatively unaffected by El Niño and where Arctic sea ice set a new lowest-extent record for a February. In those latitudes, including Alaska, recorded temperatures were at least 9 degrees Fahrenheit higher than average--"above the upper bounds" of NOAA's February Global Land and Ocean Temperature Anomalies map.
Study: Carbon Dioxide Release Occurring Faster Than At Any Other Time
A new study in the journal Nature Geoscience, which comes on the heels of NOAA's record temperature announcement, finds that humans are releasing climate-change-causing carbon dioxide 10 times faster than at any other time in the last 66 million years.
"I think to me it's completely clear we have entered a completely new era in terms of what humans can do on this planet," said Richard Zeebe, study co-author with the University of Hawaii at Manoa. "... If you look at the past and if you study the geologic record, every time when there was massive carbon release there were major changes on the planet and there were significant, large changes in the climate."
To determine how carbon dioxide levels have influenced temperatures, researchers examined warming millions of years ago in the Paleocene-Eocene Thermal Maximum (PETM) by comparing carbon and oxygen tracers, called isotopes, deep in the New Jersey sea floor. PETM is thought to be a possible stand in for the potential impacts of carbon pollutions, as it refers to a period in history when the concentration of atmospheric carbon dioxide spiked. They found that 40.8 billion tons of carbon dioxide was released into the atmosphere in 2014 but that no more than 4.4 billion tons was released in the peak year during PETM.
"Because our carbon release rate is unprecedented over such a long time period in Earth's history, it also means that we have effectively entered a 'no-analogue' state," said Zeebe. "This represents a big challenge for projecting future climate changes because we have no good comparison from the past. Our results suggest that future ocean acidification and possible effects on marine calcifying organisms will be more severe than during PETM."
Climate Change Could Be Abrupt, Trigger Dire Consequences
Burning fossil fuels at the current pace will trigger an abrupt climate shift, according to a study published in the journal Atmospheric Chemistry and Physics. Authored by retired NASA climate scientist James Hansen and 18 others, the study uses global climate modeling, paleoclimate data and modern observation of interactions between the ocean and ice sheets (specifically the Greenland and Antarctic ice shelves) to determine impacts associated with melt.
"We conclude that light freshwater added to upper layers of the ocean is already beginning to shut down North Atlantic Deep Water formation and Antarctic Bottom Water formation," said Hansen. "This will have enormous consequences in future decades, if full shutdown is allowed to occur."
The study, which stirred debate when it came out in draft form this summer, suggests that the impacts of global warming will not only happen more quickly than thought, but be more dire than envisioned. Holding temperatures to the 2 degrees Celsius of warming above pre-industrial levels would not be enough to save the planet from experiencing collapsing ice sheets and megastorms.
The paper concludes that "if the ocean continues to accumulate heat and increase melting of marine-terminating ice shelves of Antarctica and Greenland, a point will be reached at which it is impossible to avoid large-scale ice sheet disintegration with sea level rise of at least several meters. The economic and social cost of losing functionality of all coastal cities is practically incalculable."
The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University's Nicholas Institute for Environmental Policy Solutions.