Is mitigation enough?

For years the validity of the idea that global warming is occurring was questioned. Despite a large consensus among the scientific community that climate change was ‘very likely’ due to anthropogenic sources of GHGs, which equates to a >90% certainty, the small percentage of  doubt provided governments with a perfect excuse to delay their action. However, the IPCC’s latest report provides substantial evidence showing how anthropogenic emissions of GHGs are the cause of rising global temperatures. This is evidence that cannot be ignored!

Exhibit A:

Using climate models and data on all the factors (forcings) influencing the climate e.g. sun spot activity, the distance of the earth from the sun, the tilt of the earth etc, along with the rising emissions of CO2 and other GHGs, numerous models and simulations were used to determine how global temperatures would rise over time. Exhibit A shows the results from models using only natural forcings and  also results from models incorporating both natural and anthropogenic forcings. The graphs show that when anthropogenic forcings are included, the increase in temperature experienced is much higher. Therefore, climate change has been established to be partly due to the influence of anthropogenic emissions of GHGs.

Exhibit B shows that the concentrations of these GHGs have risen drastically since the 1750s, and are expected to rise further over the 21^st Century as populations continue to increase, urbanization continues and the demand for energy increases. Although the magnitude of these changes have been experienced before in the earth’s history, never have they been experienced at such speed: CO₂ concentrations are expected to increased to more than double their pre-industrial levels in the next 100 years (Nijssen, 2001).

Exhibit B

Exhibit C

Increases in global temperatures have resulted in a reduction in sea ice extent by 2.7% per decade, as shown in the satellite photos (IPCC, 2007). This decline in sea ice is occurring much faster than predicted by the climate models, as shown in Exhibit D, this has lead to a huge questioning whether the predictions from the climate models can be trusted. Have the predictions been underestimating the impact that rising global temperatures may have?

Exhibit D

So now that there is an overwhelming stock of evidence showing that humans are the cause of global warming, coupled with the fear that climate models are underestimating the impacts of climate change, and along with the enormous reaction in the media with all of the emotive images and movies (see previous blog)....you would think that this would lead to action; that governments would take the necessary steps to reduce emissions in order to curb temperature rises. Did this happen?

Exhibit E

The outcome of UN Climate Summit at Copenhagen - having all the world’s leaders along with all the world’s best scientists all in one city, where substantial evidence is given showing that if global temperatures rise by more than 2 degrees then catastrophic events will occur and yet what was achieved?

Exhibit F

More than a year later: does it look like there is any progress? 

Take a look at today's news!

Geoengineering has been described as a way to solve the symptom but not the cause. It is controversial, highly debated, can seem crazy at times (see the youtube videos in previous blog!), and is generally regarded as a taboo in academic circles. People are even afraid to just mention the idea just in case it will give government leaders another reason not to curb emissions! People have argued that it should only be used as a last resort, but each piece of evidence shown today shows that nothing else is working, so have we reached the last resort yet? (Matthews and Caldeira, 2007). Or maybe we could argue that since it is taking world leaders considerable time to make any steps or come to any conclusions, that maybe all we need is more time....could geoengineering be the solution to this?

I know I have thrown the word out quite a lot....next blog we will walk on the dark side and dare to discuss those highly controversial ideas that may become the saving grace for our planet.