Pages

Tuesday, 16 August 2016

Another record falls

Huge climate milestone falls as July 2016 becomes Earth's hottest month on record


16 August, 2016

Earth just had its hottest month yet, and the record-shattering warmth shows no signs of stopping. 

According to NASA, global average surface temperatures during July were 0.84 degrees Celsius, or 1.51 degrees Fahrenheit, above average. This beats all previous Julys, with July 2011 coming in second at 0.74 degrees Celsius above average. 


The large anomaly seen during July 2016 means that the month was the hottest on Earth since instrumental records began in 1880. 

July is typically the planet's hottest month of the year due to the fact that the Northern Hemisphere has more land area than the Southern Hemisphere, making Northern Hemisphere summer the warmest month.

July is now the tenth month in a row to be the warmest such month on record in NASA's database. 

It is now virtually certain that 2016 will beat 2015 for the dubious distinction of the hottest year on record.

NASA is not the only agency that tracks global temperatures, and its methods differ slightly from the others. 

If the National Oceanic and Atmospheric Administration (NOAA) also finds that July was the hottest such month on record and hottest month overall, it would mean that the past 15 months have each set records — an unprecedented feat in its database. 

Seasonal cycle of temperature anomalies showing July 2016 as the hottest month-to-date.
Seasonal cycle of temperature anomalies showing July 2016 as the hottest month-to-date.   IMAGE: NASA GISS VIA GAVIN SCHMIDT

The heat in the past two years has been caused by human-caused climate change with a boost from an El Niño event, which has now aded.

Yet the record heat, clearly, is continuing. 

The (presumed) record warm year of 2016 has brought flood disasters to the U.S., the latest of which is still devastating parts of Louisiana, as well as China. 
Typically hot locations, such as India, Kuwait and Iraq, set new benchmarks for what constitutes their hottest days. 

Meanwhile, the world's oceans are suffering through the longest-lasting global coral bleaching event on record.

La Niña may break the fever temporarily


Climate projections show that the odds favor a weak La Niña to develop in the tropical Pacific Ocean. If this occurs, it would be expected to hold down global temperature anomalies, and possibly interrupt the constant string of record warm months, at least for a while. 

In fact, global average temperature departures from average had been declining in recent months, though July marks an uptick compared to June, NASA found. 


Global temperature anomalies since 1956, broken up into 20-year averages compared to the 20th century baseline.

Global temperature anomalies since 1956, broken up into 20-year averages compared to the 20th century baseline. IMAGE: CLIMATE CENTRAL


You can think of El Niño as a driver pressing the gas pedal on a car all the way to the floor, while La Niña is more like a driver still pressing the gas, but at a more moderate pace.

However, even La Niña years have been warming as a result of long-term global warming, and it's possible the developing La Niña could set a record for the mildest La Niña year.

For climate scientists, what matters is the long-term trend over decades to centuries, making monthly records much less significant compared to the steady increase in temperatures throughout the 20th and 21st centuries.

The long-term record shows an unmistakable upward trend in global temperatures, with warming accelerating in the oceans and atmosphere in recent decades.


No comments:

Post a Comment

Note: only a member of this blog may post a comment.