There are huge uncertainties about the impacts of COVID-19 on 2020 CO2 emissions. If forecasts of GDP changes are accurate – and the global economy bounces back in Q3/Q4 2020 – we'd expect declines of 0.5% to 2.2%: thebreakthrough.org/issues/energy/… 1/5 
The upper bound (0.5%) uses JP Morgan's optimistic projection that the GDP expands dramatically during the recovery to make up for lost time. The lower bound (2.2%) assumes it just recovers back to pre-pandemic levels in Q3/Q4. 2/5
This decline would be similar to that seen during the 2009 global financial crisis, when emissions fell by 1.5% compared to 2008. 3/5
This represents a lower bound; much larger declines are possible if economic shutdowns are prolonged and recovery is slow. Similarly, if the pandemic lasts well beyond Q2 2020 and/or reemerges in the fall, economic impacts and emission reductions could be much more severe. 4/5
There's no climate silver lining to COVID-19. It'll slow the rate of deployment of clean energy and electric vehicles, delay decarbonization as climate becomes a lower priority for policymakers, and if past recessions are any sign, emissions will snap back up post-recovery. 5/5
@MLiebreich suggests a 5% reduction in emissions is possible in 2020. This would be likely if current social distancing measures do not succeed in substantially reducing infections over the next three months or if it comes roaring back in the fall.
