Significant warming now inevitable, even if carbon release were cut to zero

As we fiddle, the impacts of climate change grow, and new research says they are now inevitable.

A new Canadian study shows that even if we reduce all carbon emissions to zero, which of course we won't, there is already so much greenhouse gas in the atmosphere that 3.6 degrees Fahrenheit (2 degrees Celsius) of warming is likely unavoidable by 2100.

The unstated extension is that much higher temperature rise is probable. And of course with it, direct impacts to Hawai`i, which include the rising sea levels, changes in rainfall patterns, acidification of the oceans, and all the rest.

What's the take-away from this? It's another heavy brick in the wall. We have a moral obligation to our grandkids to moderate our carbon-spending ways, and we have a fiduciary responsibility as citizens to plan strategically for the expected outcomes.

One of the purposes of this blog is to highlight the science that most media miss. This is an example.

The research is an early report from climate projections that will be part of the 2014 Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Here is the link.

These researchers strictly avoid hysterical language, even if that might be appropriate in this case. Their conclusion is understated and grim: “The results of this study suggest that limiting warming to roughly 2°C by the end of this century is unlikely since it requires an immediate ramp down of emissions followed by ongoing carbon sequestration in the second half of this century.”

They have formed a new set of predictions based on the best available and newest data on such things as “carbon dioxide and other greenhouse gases, aerosols, land use change, and the flow of carbon between the atmosphere and the underlying ocean and land surface.”

They conclude that the absolute best case for the next nine decades is that we'll face 2 degrees Celsius of warming. And since nobody believes limiting carbon emissions to zero is even possible, the actual number will be higher.

You're not reading this information much anywhere else. It's complicated, and since complexity is the enemy of understanding, the eyes of writers at most media outlets glazed over, or bypassed it altogether.

That's perhaps not surprising. The title of the paper doesn't give much of a clue about what's in it: Carbon emission limits required to satisfy future representative concentration pathways of greenhouse gases.

© Jan TenBrugggencate 2011

Here's the citation: Arora, V. K., J. F. Scinocca, G. J. Boer, J. R. Christian, K. L. Denman, G. M. Flato, V. V. Kharin, W. G. Lee, and W. J. Merryfield (2011), Carbon emission limits required to satisfy future representative concentration pathways of greenhouse gases, Geophys. Res. Lett., 38, L05805, doi:10.1029/2010GL046270.

These are the authors: V. K. Arora, J. F. Scinocca, G. J. Boer, G. M. Flato, V. V. Kharin, W. G. Lee, and W. J. Merryfield: Canadian Centre for Climate Modelling and Analysis, Environment Canada, University of Victoria, Victoria, British Columbia, Canada; J. R. Christian: Canadian Centre for Climate Modelling and Analysis, Environment Canada, University of Victoria, Victoria, British Columbia, Canada and Fisheries; and Oceans Canada, Institute of Ocean Sciences, Sidney, British Columbia, Canada; K. L. Denman: Canadian Centre for Climate Modelling and Analysis, Environment Canada, University of Victoria, Victoria, British Columbia, Canada; and VENUS, University of Victoria, Victoria, British Columbia, Canada.