SOURCE: The Guardian

DATE: January 13, 2020

SNIP: The heat in the world’s oceans reached a new record level in 2019, showing “irrefutable and accelerating” heating of the planet.

The world’s oceans are the clearest measure of the climate emergency because they absorb more than 90% of the heat trapped by the greenhouse gases emitted by fossil fuel burning, forest destruction and other human activities.

The new analysis shows the past five years are the top five warmest years recorded in the ocean and the past 10 years are also the top 10 years on record. The amount of heat being added to the oceans is equivalent to every person on the planet running 100 microwave ovens all day and all night.

Hotter oceans lead to more severe storms and disrupt the water cycle, meaning more floods, droughts and wildfires, as well as an inexorable rise in sea level. Higher temperatures are also harming life in the seas, with the number of marine heatwaves increasing sharply.

The most common measure of global heating is the average surface air temperature, as this is where people live. But natural climate phenomena such as El Niño events mean this can be quite variable from year to year.

“The oceans are really what tells you how fast the Earth is warming,” said Prof John Abraham at the University of St Thomas, in Minnesota, US, and one of the team behind the new analysis. “Using the oceans, we see a continued, uninterrupted and accelerating warming rate of planet Earth. This is dire news.”

We found that 2019 was not only the warmest year on record, it displayed the largest single-year increase of the entire decade, a sobering reminder that human-caused heating of our planet continues unabated,” said Prof Michael Mann, at Penn State University, US, and another team member.

The analysis, published in the journal Advances In Atmospheric Sciences, uses ocean data from every available source. Most data is from the 3,800 free-drifting Argo floats dispersed across the oceans, but also from torpedo-like bathythermographs dropped from ships in the past.

The results show heat increasing at an accelerating rate as greenhouse gases accumulate in the atmosphere. The rate from 1987 to 2019 is four and a half times faster than that from 1955 to 1986. The vast majority of oceans regions are showing an increase in thermal energy.

“The data we have is irrefutable, but we still have hope because humans can still take action,” he said. “We just haven’t taken meaningful action yet.”