The “Hockey Stick” – Augmented

Posted on March 10, 2013


The journal Science has just published an update on Michael Mann’s “hockey stick” graph by a new team of scientists, who, by combining 73 sets of globally distributed records have extended the reconstruction of past global temperatures back 11,300 years.  Michael Mann’s hockey stick only went back 1500 years. 

The new reconstruction by Marcott et al. reaches back to the beginnings of agriculture, encompassing the entirety of neolithic civilization and after.

The following graph combines the new reconstruction with Mann’s original “hockey stick” graph.  That incredible uptick in temperatures at the end is a little unnerving, but it’s even worse if you remember that it only brings the temperature increase up to today.

marcott-B-MJ hockey stick

Most of the warming that’s in the works if humanity doesn’t change its dependence on fossil fuels simply hasn’t happened yet.  Some scientists have made estimates of what that warming will add up to and Joe Romm from Climate Progress has added those estimates to Marcott et al‘s graph to show what that looks like. 

Here is Joe Romm’s graph:

Carbon-Final Joe Romm

Now that’s really scary.  The red line represents the warming that scientists are predicting, according to current trends in fossil fuel use.

By the time we have whistled past, or even near, 4oF of warming, we are already in deep doo-doo as a civilization.  As you can see, the graph doesn’t stop at 4oF of warming.

A slope that steep and high represents steep and high changes to the environment.  It’s mighty hard to adapt to changes that are going on so fast, so a lot of our fellow inhabitants on this planet are going to be in real trouble too.  Many are expected to die off.

There is nothing in these charts that assures me that we have time left to put off action until the next election cycle.