Regular readers know that I try not to be alarmist about the issues I write about. I have a point of view, but try to back up my assertions with factual information you can check for yourself. So when I tell you that there is a new credible study that warns of an impending climate disaster, you should take notice. The study argues that the serious effects of climate change — sea level rise of several feet, followed by increases so large they would force humanity to flee the coasts — will occur over the next 50 years, not over the course of centuries as climate scientists currently believe.
The source is highly credible. Lead author in the study is Dr. James Hansen, retired NASA scientist and director of the Columbia University Climate Center. The paper, published in the European journal Atmospheric Chemistry and Physics, was co-authored with 18 other scientists.
And when I say that Dr. Hansen is credible, you should know that he gained fame in 1988 when he warned Congress that global warming had already begun. He was ahead of the scientific consensus at the time, but it became clear in retrospect that Earth had been in the midst of a period of rapid global warming at the time he testified.
Cataclysmic sea level rise
The study, released today, concludes that a 2° Celcius global temperature rise from pre-industrial levels will cause:
- Cooling of the Southern Ocean, especially in the Western Hemisphere;
- Slowing of the Southern Ocean overturning circulation, warming of the ice shelves, and growing ice sheet mass loss;
- Slowdown and eventual shutdown of the Atlantic overturning circulation with cooling of the North Atlantic region;
- Increasingly powerful storms; and
- Nonlinearly growing sea level rise, reaching several meters over a timescale of 50–150 years.
According to the study, these predictions, especially the cooling in the Southern Ocean and North Atlantic with markedly reduced warming or even cooling in Europe, differ fundamentally from existing climate change assessments.
Current efforts insufficient
This is extremely disturbing in light of the landmark climate agreement reached in Paris last December. In that agreement 195 countries agreed to reduce greenhouse gas emissions as soon as possible and to keep global temperature increases “well below” 2°C (3.6°F) and to pursue efforts to limit it to 1.5°C. If Hansen’s study is correct, that won’t be enough.
What’s more, global temperatures seem to have begun a period of rapid rise. The year 2015, like 2014, was the warmest year on record. And both January and February have been the warmest in history. As shown in the chart below, we have blown past a 1°C increase, and global 12-month average temperature is now 1.177°C above pre-industrial levels.
Before you sell your beachfront home, you should be aware that there is not universal acceptance of Dr. Hansen’s findings. But the study is now public, and it will be the topic of a furious public debate among scientists. Dr. Hansen has a track record of being correct, and his work underscores that we need to take our heads out of the sand and address climate change as a critical public policy issue.
I recommend that you watch the 15 minute video below, in which Dr. Hansen discusses the study. It’s dense at times, but it is a good primer on his work and will help you understand the study. We ignore it at our peril.