Children should be introduced to our remarkable planet
while young, when their curiosity is easily stoked. If you have young
ones ready to sit still for 6-9 minutes, I heartily recommend the series
Every Rock Has a Story
by Boston College Prof. Ethan Baxter. It is wonderful for inspiring
wonder and curiosity, and for introducing the scientific method, how
scientists try things, make mistakes, and learn from them. Children
will be comfortable with Ethan, who has a lot in common with Mr.
Rogers. Parents can check his 19-minute teacher/parent guide.
Curiously, at almost exactly the same moment
that I received an e-mail from Ethan Baxter, I received one from the
Rock Whisperer, my friend Paul Hearty, with a copy of his current
paper[1] on rocks in South Africa. He and co-authors show that in the
Mid-Pliocene (about 3 million years ago), when atmospheric CO2
was about the same as today, it was a few degrees warmer and sea level
was 15-30 meters higher (50-100 feet). One of Paul’s co-authors is
Maureen Raymo, the new Director of Columbia’s Lamont-Doherty Earth
Observatory, who dubbed Paul the Rock Whisperer for his remarkable ability to read the story in the rocks.
In 2006, when I was concerned that the IPCC projections of sea level
rise were unrealistically conservative, I suspected that something was
wrong with the ocean models that IPCC was relied on. For one thing, the
models did not properly include the cooling effect of ice melt on the
North Atlantic and Southern Oceans. So we ran climate simulations with
our coarse-resolution global model, and were startled by the result: we
found that the world was on the verge of shutting down both the Southern
Ocean and North Atlantic overturning circulations, with enormous
potential consequences for future sea level because of amplifying
feedbacks for Antarctic ice.
This would be a hard story to sell, given the coarse resolution of our
model, and the fact that our result seemed to differ from all the other
models. And why did Earth’s history not reveal such rapid
feedback-driven change in the past? That’s when I discovered the papers
of Paul Hearty for the last interglacial period, the Eemian, about
120,000 years ago, when global temperature reached levels perhaps as
much as 1-2°C warmer than the preindustrial (1880-1920) level.
Hearty’s reading of the rocks painted a
picture of the Eemian that was consistent with what we were finding in
our climate modeling. We needed to develop that story, so we started to
work with Paul Hearty, but first we needed an explanation for what was
wrong with the ocean models.
The most crucial information about the ocean models was provided by
observations of heat uptake by the oceans. Here the expert, the ocean
heat whisperer if there is such a thing, was a young post-doc, Karina
von Schuckmann, with whom we began to collaborate in about 2010.
When we published the paper Ice Melt, Sea Level Rise and Superstorms[2] it was greeted by some in the community in the same way that our 1981 paper in Science[3] and
1988 congressional testimony[4] were greeted. Seth Borenstein, lead
science writer for the Associated Press, was told by five of his six top
climate science experts that he should not even write about this paper,
and he did not. This year, we have obtained strong confirming evidence
of the principal conclusions of our paper. Because I am within months
of finishing Sophie’s Planet, I will describe the results first in the book.
Speaking of rocks, the 1,000-ton boulder that Anniek is standing beside
in the photo was washed up to the top of a hill on Eleuthera by waves
from a powerful storm, aided by a higher sea level. That story will be
in the book.
There is still a lot of hard science to do. How much time do we have to
make the changes that are needed to avoid catastrophic outcomes, such
as unacceptably large sea level rise? What are the most effective
actions? Panic is counterproductive. Plenty to discuss.
Finally, I apologize for the slightly flippant paragraph that I added at
the end of Chapter 23, which some people found to be confusing. It was
a bit of an insider comment meant to refer to my bad decision to 1981
to move GISS into NASA Earth Sciences, rather than NASA Space Sciences.
I will fix that paragraph to clarify the story.
You can sign up for our monthly global temperature updates here.
You can sign up for my other Communications here.
I opened a Twitter account @DrJamesEHansen, (https://twitter.com/drjamesehansen), but I am focusing mainly on finishing the book.
[2] Hansen, J., M. Sato, P.
Hearty, R. Ruedy, M. Kelley, V. Masson-Delmotte, G. Russell, G.
Tselioudis, J. Cao, E. Rignot, I. Velicogna, B. Tormey, B. Donovan, E.
Kandiano, K. von Schuckmann, P. Kharecha, A.N. Legrande, M. Bauer, and
K.-W. Lo: Ice
melt, sea level rise and superstorms:/ evidence from paleoclimate data,
climate modeling, and modern observations that 2 C global warming could
be dangerous Atmos. Chem. Phys., 16, 3761-3812, 2016.
[3] Hansen, J., D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell: Climate impact of increasing atmospheric carbon dioxide. Science, 213, 957-966, 1981.
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