At the preparatory meetings for COP21 in Lima, Peru, delegates from countries that are most vulnerable to the impacts of climate change proposed changing the global temperature target from 2-degree Celsius to 1.5-degree Celsius.
Over the advice of climate scientists, the change was adopted as an aspirational goal.
Hereafter, the targets will be qualified as “well below 2-degree Celsius above pre-industrial levels with efforts to limit temperature increase to 1.5-degree Celsius,” to use the language of the Paris Agreement.
The Industrial Revolution began in England in about 1750. However, the Intergovernmental Panel on Climate Change (IPCC) had been using 1875 as the base year for calculating global temperature.
Dr. Michael E. Mann, the director of the Penn State Earth System Science Center has determined that from 1875 our net carbon budget is about 3000 gigatons of which we have used about 2000 gigatons or approximately two-thirds.
Using another metric, the limit for 2-degree Celsius is 450 parts per million of carbon. The pre-industrial levels are 350 ppm. The current levels are 440 ppm, increasing by about 2.1 ppm every year. We will reach 450 ppm in about 20 years.
In an article that appeared in Scientific American last year, Dr. Mann, using 1750 as the base year, estimated that we will cross the climate danger threshold in 2036.
This gives us very little time to make the transition from fossil fuel to carbon free energy.
What must be done?
(1) All countries should fulfill, as best they can, the pledges that they made in Paris to reduce their carbon emissions. Inadequate as they are, it will at least help stabilize carbon concentrations in the atmosphere.
(2) Every country should consider a carbon tax. An harmonized price of carbon should be taken up and approved if possible, in the 2020 meeting. If a uniform price cannot be adopted, for whatever reason, each country should promulgate and enforce a national carbon price. The revenue raised should be used for adaptation and mitigation measures.
(3) The public and private sectors should collaborate on technologies that will “decarbonize” our economies.
(4) And finally, everyone should be upfront and transparent in their efforts to attain the 1.5-degree Celsius goal.
Carbon capture and sequestration (CCS) should be the object of a Manhattan Project-type approach.
Two CCS technologies are worth serious consideration.
The first involves planting trees, tall grasses, cellullosic shrubs, etc. to absorb carbon dioxide through photosynthesis. They will then be harvested and processed as fuel for thermal power plants that are equipped to capture the carbon dioxide that they will emit, which will then be liquefied for long-term storage underground or used as raw material for new products.
The second is a machine that will capture atmospheric carbon dioxide for sequestration in rock formations, saline aquifers, and empty oil and gas wells.
Such machines are already being used, albeit on a small scale, in Switzerland.
The aspects of this technology that need to be examined is whether it could be geoengineered and whether the storage sites could be made leak-proof.
Are these disruptive technologies?
We do not know. In quantities that will be significant, bioenergy crops would need enormous land areas that will compete with food production. Huge suction machines could have still unknown effects on weather and climate.
It is necessary to educate and train more climate scientists and skilled workers in the various disciplines of climate mitigation and control.
When COP22 and COP23 are convened in 2020 and 2030 respectively for stock taking and for ramping up country pledges, the matter of finance must be revisited and tackled head-on.
Differentiation should be defined more precisely to make cost sharing acceptable.
We have only up to the middle of the century to attain the 2-degree Celsius temperature target and attempt to roll it back to as close to 1.5-degree Celsius as we are able.
Else, the next generation will inherit a 3-degree Celsius world.