Founders Pledge has recently completed a large report on climate change, which recommends two new cost-effective climate change charities - the Clean Air Task Force and Coalition for Rainforest Nations. This is on our research page here (which also has a report on mental health and will be supplemented with a number of other in-house reports over the next few months). I know some EAs are interested in climate change and it is something we are often asked about. We have been relying on old GWWC research for a while so this should be a useful update.
It may also be of interest because both charities work on policy rather than doing direct work. Finally, there is some discussion of why we do not recommend Cool Earth.
Edit: there is also a discussion of the link between nuclear power and nuclear weapons that may be of interest to ex risk people
I think that a focus on partisan politics, and one that especially tries to narrow its scope to Republicans, suffers from lacking a firm framework of how this is supposed to create a specific outcome. One individual Republican representing a heavily Democratic district on the front lines of sea level rise discussing a carbon tax, with almost no real support from the rest of his caucus, is an aberration.
Across the board, Republican politicians oppose carbon taxes, the House took such a vote this week and the efforts by CCL to provide cover to the Republicans in the Climate Solutions Caucus who voted for a resolution opposing carbon taxes seems like the very definition of ineffective.
If there's a case for engagement in the political process around climate change, it's looking at the risks of climate change and determining the most effective strategies to adapt to them. For example, perhaps a certain degree of sea level rise is baked into the cake and an effective policy response is reducing exposure of properties to this risk. So coastal resiliency and flood insurance reform would make sense. However while some of the values of properties and communities involved in, say, significant flooding in Miami may be high, I don't know if it's that significant in any sort of global sense.
It's not really narrowing its scope to Republicans. It's a non-partisan organization with a policy that has bipartisan support. It's just been especially important to talk about Republican support since Republicans have been largely denying climate change up until very recently.
A carbon tax is required to solve climate change (http://news.mit.edu/2016/carbon-tax-stop-using-fossil-fuels-0224) and only government has the power to levy a tax.