Archives par mot-clé : CO2 Storage

Nature Has Been Removing Excess CO2 4X Faster than IPCC Models

by Dr. Roy Spencer, February 5, 2020 in WUWT


Note: What I present below is scarcely believable to me. I have looked for an error in my analysis, but cannot find one. Nevertheless, extraordinary claims require extraordinary evidence, so let the following be an introduction to a potential issue with current carbon cycle models that might well be easily resolved by others with more experience and insight than I possess.

Summary

Sixty years of Mauna Loa CO2 data compared to yearly estimates of anthropogenic CO2 emissions shows that Mother Nature has been removing 2.3%/year of the “anthropogenic excess” of atmospheric CO2 above a baseline of 295 ppm. When similar calculations are done for the RCP (Representative Concentration Pathway) projections of anthropogenic emissons and CO2 concentrations it is found that the carbon cycle models those projections are based upon remove excess CO2 at only 1/4th the observed rate. If these results are anywhere near accurate, the future RCP projections of CO2, as well as the resulting climate model projection of resulting warming, are probably biased high.

 

Introduction

My previous post from a few days ago showed the performance of a simple CO2 budget model that, when forced with estimates of yearly anthropogenic emissions, very closely matches the yearly average Mauna Loa CO2 observations during 1959-2019. I assume that a comparable level of agreement is a necessary condition of any model that is relied upon to predict future levels of atmospheric CO2 if it is have any hope of making useful predictions of climate change.

In that post I forced the model with EIA projections of future emissions (0.6%/yr growth until 2050) and compared it to the RCP (Representative Concentration Pathway) scenarios used for forcing the IPCC climate models. I concluded that we might never reach a doubling of atmospheric CO2 (2XCO2).

But what I did not address was the relative influence on those results of (1) assumed future anthropogenic CO2 emissions versus (2) how fast nature removes excess CO2 from the atmosphere. Most critiques of the RCP scenarios address the former, but not the latter. Both are needed to produce an RCP scenario.

I implied that the RCP scenarios from models did not remove CO2 fast enough, but I did not actually demonstrate it. That is the subject of this short article.

What Should the Atmospheric CO2 Removal Rate be Compared To?

Continuer la lecture de Nature Has Been Removing Excess CO2 4X Faster than IPCC Models

Negative CO2 Emissions

by Kevin Kilty, January 24, 2020 in WUWT


An article in the January 2020 Issue of Physics Today (1) presents an interesting and very readable overview of methods to capture and store away CO2 emissions. The purpose of this guest blog is to summarize a few key points the paper makes, and add some commentary. WUWT has covered some of this same territory recently here and here.

Motivation

Of course, the motivation for negative emissions technologies (NETs), or CO2 capture, is to bring atmospheric CO2 back to safe levels. Although the article fails to mention what safe means in this context, and what levels are unsafe, it alludes to melting polar ice and methane escaping from melting permafrost as consequences of unsafe climate. Nothing unusual here. Despite relegating its case for an unsafe future to such enterprises as the IPCC, the article does provide some insight into the cause of what seems to be the current “crisis” mentality. It is 1.5°C temperature rise goal of the 2015 Paris agreement. As readers of WUWT already know, this is not a 1.5°C increase from now, but rather from an estimated pre-industrial level — meaning that two-thirds of that margin is already gone and we have but 0.5°C left to work with. I suspect most people do not understand this subtle point.

Eventually the article makes a brief excursion into more phenomena by which climate change would become unsafe — forest fires, droughts, and sea level rise. All of this is also familiar to WUWT readers.


Technologies Involved