For discussing climate/energy things that are not the topic of other posts (hint, hint). E.g:
How (in)consistent is the instrumental temperature record with a climate sensitivity between 2 and 4.5 degrees (per doubling of CO2)? Turns out, within the admittedly large uncertainties they are entirely consistent (based on Ramanathan and Feng, 2009):
Global average surface temperatures have increased by about 0.75 degrees Celsius since the beginning of the industrial revolution, of which ~0.6 °C is attributable to human activities. The total radiative forcing by greenhouse gases is around 3 W/m2, with which we have ‘committed’ the planet to warm up by 2.4 °C (1.6-3.6 °C), according to a climate sensitivity of 3 °C (2-4.5 °C) for a doubling of CO2. The observed amount of warming thus far has been less than this, because part of the excess energy is stored in the oceans (amounting to ~0.5 °C), and the remainder (~1.3 °C) has been masked by the cooling effect of anthropogenic aerosols.
Dana over at SkS has an excellent post on this as well, using slightly different numbers and accounting for uncertainties. Over at the previous thread, RickA makes the common mistake of omitting the negative aerosol forcing and the ocean thermal inertia.
On low carbon technologies I don’t have terribly much to add at the moment, except to point to previous posts on technology (including lots of pointers to literature and/or other articles).