GSI Seminar Series: Femke Nijsse ' Emergent constraints on climate sensitivity from historical warming and models' and 'Kirsten Lees ' Peatland Resilience'

Speaker one: 
Dr Femke Nijsse (University of Exeter)
‘Emergent constraints on climate sensitivity from historical warming and models'

Abstract
Climate sensitivity to carbon dioxide remains a key uncertainty in projections of future climate change, both on a transient timescale relevant for the Paris agreement and in the long-term response. Many of the latest CMIP6 ESMs have larger climate sensitivities than the likely range of the IPCC’s Fifth Assessment Report. We show that these are inconsistent with observed trend of global warming from 1975 onwards. This is a period when the signal-to-noise ratio of the net radiative forcing increases strongly, so that uncertainties in aerosol forcing become progressively less problematic. With an emergent constraint approach, we give a more probable estimate of climate sensitivity.
Towards the end of the talk, I’ll give a teaser into my current research of modelling the energy transition in a project focussed on China, India, and Brazil. With dramatic decreases in the price of solar and wind, and their fast penetration into the grid, it is important to model the issue of variability and intermittency well, ensuring there are enough sources of flexibility.  But how to model this in a simple way?

Speaker two:
Dr Kirsten Lees (University of Exeter)
'Peatland Resilience.'

Abstract
Peatlands are important for many ecosystem services including carbon storage, flood management, biodiversity, and clean water; but the resilience of these ecosystems in the face of climate change and human land use is uncertain. Resilience can be defined as the rate at which a system recovers from perturbation, and can therefore be estimated by monitoring the time taken for a measure of ecosystem health to return to within its normal range following a disturbance event. Disturbance events can include natural occurrences such as drought or wildfire, or human impacts such as peat cutting or managed burns. In this talk I will present how satellite data can be used to detect disturbance events and to monitor recovery times and therefore estimate peatland resilience.