Cutting CO2 Emissions is Necessary but Not Sufficient

Former NASA climate scientist James Hansen and colleagues recently published an article that lays out why cutting CO2 emissions ais necessary but is no longer sufficient to reduce concentrations of greenhouse gasses (GHG) to acceptable levels.  Among their findings is that “…large CO2 extraction from the air is needed and a halt of growth of non-CO2 climate impacts to achieve the temperature stabilization…” They rightly point out that developed nations have an obligation to assist those nations since they haven’t contributed much to the problem but bear a disproportionate share of its impacts.

They also point to a role for demand-side changes that provide GHG mitigation. For example, reducing meat and dairy production is needed to reduce GHG emissions from agriculture.  Other agriculture and land use changes (in addition to changes in our diets), include reducing food waste and changes in wood use “…have substantial mitigation potential, but they remain under-researched and poorly quantified.”


Hansen and his co-authors note that unless rapid emission reductions are initiated soon, pulling CO2 out of the atmosphere using demand-side strategies will require more extreme changes to current agricultural and forestry practices. They also sounded a warning that if “large” [emphasis added] fossil fuel emissions continue, deamnd-side methods of removing existing CO2 from the atmosphere will require more costly industrial scale CO2 extraction.

Comments

Post a Comment

Popular posts from this blog

Is California About to Require that by 2045 All Electricity Must Come from Renewables?

Image
Not exactly. Let me explain. Our lack of even the most basic understanding of how the elecricity system operates (explained below) allows us to mistakenly imagine we are taking actions that will shut down CO2 emitting generators. A number of headlines read something like "California Poised To Require All Its Electricity To Come From Renewables."  SB100  appears to be a bit more complicated, however.  Plus, electricity complies to the laws of physics, not the laws we mere mortals devise. Hoefully, this post will identify several important implications of these distinctions. Recognize that electrons (what electricity consists of) going over the wires thorughout California flow from all generators located everywhere within what’s called the Western Interconnect (WECC).  Electrons are already present throughout all the electric wires in every building in every community at every moment in time. When you flip a light switch on, more electricity gets generated ...
Read more

Coal-Fired Electricity Will Continue to Serve Portland

Contrary to what the 2017 Update states, SB1547 does not require that coal plants be phased out by 2035.   It also does not require any phasing out of coal-fired electricity from helping to serve our demand for electricity.   While it does increase the Renewable Performance Standards (RPS) in the out years, reaching 50% by 2050, this applies only to two utilities: PGE and PacifiCorp.   Even then, the requirement may be met through the purchase of Renewable Energy Certificates (RECs) from across the United States.   As a result, the electricity entering homes and businesses in Portland will continue to include carbon-based generation, including coal.   There is a second reason why carbon-based fuels, including coal, will continue to be delivered to Portland’s homes and businesses since coal will remain a significant component of the West Coast power system of which PGE and PacifiCorp are a part. If you are interested in this issue, here are seve...
Read more

100% Renewables Study Implies Historic Construction Program

Image
The often cited study by Mark Jacobson et. al. that asserts it's economic to replace every fossil fuel use with either electricity from wind, water, and sun (WWS-only) or hydrogen produced using WWS-only in 139 countries over the next 33 years implies a massive construction program the likes of which we may not have ever seen. I find it useful to compare the implied construction program to what we have experienced in the recent past. Click  here  to see his paper on the 50 U.S. states. Over the next 33 years, even under his extraordinary drop in total electric load, he envisions approximately 5.8 million MW of new generation are needed (plus an additional 600GW for peaking and system stability). He reports that as of 2013, 2.71% (of 5.8 million MW) is currently installed, or approximately1.6 million MW. Such quantities indicate an extraordinary construction program, especially since the U.S. installed capacity rose by only about 177,400MWs over the eight year pe...
Read more