NOAA released its Global Land And Sea temperature and precipitation analysis for April on May 18.
With El Niño beginning to fade, climatologists and politicians hoped for a reduction in the rate of global temperature increase.
No such luck.
April Temperature By The Numbers
The average global land and sea temperature for April, 2016 was 14.8°C (58.6°F).
This was 1.1°C (2.0°F) above the 20th century average.
It was the twelfth consecutive month of new global land and sea temperature records.
It was also the fifth month in a row with a departure from the 20th century average of more than one degree Celsius.
Global Temperature Patterns For April
April, like the two previous months, as well as the January to April period, produced a clean sweep of temperature records:
- Combined global land and sea
- Global land and global sea
- Northern hemisphere in each category (land, sea, and land and sea combined)
- Southern hemisphere in each category
Overall, a large part of the world had record high temperatures, while nowhere was there a record low. Here are some of the highlights:
- The feature that stands out is the large part of the Indian Ocean that had record high temperatures. The area of record temperatures extended eastward into Asia, Indonesia, Australia, and adjacent waters.
- Nearly half of South America had record high temperatures.
- Substantial parts of northern Africa, southern Europe, and eastern Australia set records.
- The only land areas that were below normal were the southern tip of South America and part of northeastern Canada.
- The Anti-blobs, cold patches in the northern Atlantic and Pacific Oceans, were still present but appeared to be weakening.
What Is The REAL Increase In Global Temperature?
As Decoded Science frequently notes, statistics are squishy things that can be deformed in almost any desired way. Climatological changes are especially difficult to pin down because they are small. Much has been made by climate change deniers of the change in temperature beginning in 1998, an anomalously warm El Niño year. Finally we have something to agree on. Let’s measure the change in temperature from 1998.
2016 is almost identical to 1998 as far as water temperatures in the Pacific Ocean are concerned. Comparisons between the two years should give us a reliable estimate of the global temperature increase over a significant time period. To smooth things out a little from monthly readings, we can use the January to April period.
The increase in temperature from January-April, 1998 to January-April, 2016 is 0.45°C (0.81°F). At this rate, the temperature will increase 2.5°C (4.5°F) in the next century. The stated goal of the recent Paris climate conference (COP21) is to keep the increase in the average global temperature under 2.0°C., and the temperature has already risen more than half that amount.
At the rate of increase in temperature from the last El Niño to this one, the temperature will have risen 2°C from the long-term average by 2048. That will be when atmospheric scientists fear catastrophic climate change could begin.
How We Doin’ So Far?
Though the climate change agreement aims to reduce emissions of carbon dioxide, the main cause of global warming, only a few countries have begun voluntary reductions. Many countries are still full-speed-ahead on building coal-fired power plants, and atmospheric carbon dioxide continues to increase at an accelerating rate. Pre-industrial carbon dioxide levels were around 280 parts per million (ppm), and recent readings from Mount Mauna Loa in Hawaii, regarded as reliable by atmospheric scientists, show levels above 400 ppm (April average was near 407 ppm).
The ratification process for the Paris agreement has just begun, and there is considerable sentiment in the United States for re-negotiating it or scrapping it entirely. Even at its best, the agreement sets up mainly voluntary procedures to reduce emissions, and most experts view it as far too weak to keep the temperature from climbing to dangerous levels.
Why Do We Care If The Earth Warms A Couple Of Degrees?
It is true that if the Earth warmed a uniform two degrees Celsius, that would have a relatively minor effect on humans: Diseases would spread and crops would be affected; sea level would rise. But overall the changes could be accommodated with minimal disruption of lives. However, the changes will not be evenly spread. Already we see the arctic warming at many times the rate of the rest of the world. In the case of the arctic, there is the obvious feedback of water having much lower albedo (ability to reflect sunlight) than ice. As the ice melts, more of the sun’s heat is absorbed rather than reflected.
Other feedbacks will not be so obvious, and no one is betting on what they will be. Atmospheric circulations could undergo drastic changes: some places could warm tens of degrees while others get colder; floods and droughts could disrupt agriculture and lead to famine. Storms could become much more severe. Glaciers could melt rapidly and cause sea level to rise tens of feet rather than tens of inches.
These are not predictions — just possibilities. The only prediction that Decoded Science is willing to make is that the weather of the future will be different from the weather of the past.
Decoding Science. One article at a time.