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Showing posts with the label IPCC

How much CO2 could be removed by planting trees?

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Credit: NASA This article in the guardian points to some recent research.  The article begins: Planting billions of trees across the world is one of the biggest and cheapest ways of taking CO2 out of the atmosphere to tackle the climate crisis, according to scientists, who have made the first calculation of how many more trees could be planted without encroaching on crop land or urban areas. As trees grow, they absorb and store the carbon dioxide emissions that are driving global heating. New research estimates that a worldwide planting programme could remove two-thirds of all the emissions from human activities that remain in the atmosphere today, a figure the scientists describe as “mind-blowing”. and goes on to quote the lead scientist from ETH Zürich saying "This new quantitative evaluation shows [forest] restoration isn’t just one of our climate change solutions, it is overwhelmingly the top one" Let's test this claim with two tools everyone has at their disp

Why 2050 is too late

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In 2018 the Intergovernmental Panel on Climate Change produced a report on 1.5 C of warming .  This is considered a level of warming that is 50% likely to trigger a tipping point beyond which further warming will be beyond human control. According to the report: "Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate" Unfortunately, that's been taken by our politicians to mean we've got until 2050 to zero our emissions. Let's see if this is true: According to section C.1.3 "C.1.3. Limiting global warming requires limiting the total cumulative global anthropogenic emissions of CO2 since the pre-industrial period, that is, staying within a total carbon budget (high confidence). By the end of 2017, anthropogenic CO2 emissions since the pre-industrial period are estimated to have reduced the total carbon budget for 1.5°C by approximately 2200 ± 320 GtCO2 (medium confidence). The associated remaining budget i

SR15 and BECCS

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Bio-Energy Carbon Capture & Storage I've been reading a lot about climate change recently.  I'd like to help move this issue further up the political and news agenda, but the problem is that any claim can easily be dismissed as coming from a fringe source and countered with a claim from another source.  So it really helps that the IPCC exists and makes regular reports to the UN.  No one can dismiss the IPCC as "fringe".  Many scientists believe they take a too conservative line for political reasons.  But this too is quite handy as it means that when the IPCC say "we need to do at least this", then everyone(*) agrees we need to do at least that. I've been reading the IPCC's Special Report: Global Warming of 1.5 ºC Summary for Policymakers .  The UN asked the IPCC to report on the differences between a +1.5ºC future and a +2ºC one, and in 2018 they did.  A lot of the report consists of bland qualitative statements along the lines of &quo