Post on 07-Jul-2022
Pep CanadellCSIRO, Global Carbon Project
Canberra
Carbon Cycle Fundamentals, the Role of Negative Emissions & simulating
their response
andrew.lenton@csiro.au
Andrew LentonCSIRO Oceans and Atmosphere
Where are we & the growing need for Neg
Emissions
Present Day Anthropogenic Perturbation
Keller Lenton et al, Current Climate Change Reports 2018
Current Emissions & Paris
Decarbonization Rates
Peters et al. 2013, NatureCC; Global Carbon Budget 2016Global Carbon Project 2017; Mitigation curves after Raupach et al. 2014, NatureCC
Negative Emissions or Carbon Dioxide Removal
• The removal of carbon dioxide from the atmosphere• CDR: Carbon Dioxide Removal • Not avoided emissions
Afforestation/Reforestation Direct CO2 RemovalBiofuels with CCS
Canadell & Schulze 2014, NatCom
Negative Emissions Technologies
Not all sectors can be easierly decarbonised(> 1/3 total GHGs)
Non-CO2 EmissionsCO2 Emissions CO2 Emissions
Already counting on these:
Neg Emissions have long been of our low emissions pathways (IPCC)
Bioenergy Carbon Capture and Storage (BECCS)
Increasingly reliant on Neg Emissions - emissions on credit.
Can’t get to Paris without NE.Anderson & Peters, 2016
How will the earth system (carbon cycle)
respond to Negative Emissions?
Reducing Emissions to limit warmingNet Positive Emissions with CDR
Net Negative Emissions with CDR
Anderson & Peters, 2016
Net Positive Emissions
Carbon cycle response to CDR
Net positive emissions with CDR Net negative emission
Natural sinks weaken Sinks become sources of CO2
These feedbacks are not well quantified !
Carbon Cycle Feedbacks Oppose CDR!
Keller Lenton et al, Current Climate Change Reports 2018
Modelling the Earth System Response to Negative Emissions
An initiative that brings together a suite of Earth System Models (ESMs) and Earth System Models of Intermediate Complexity (EMICs) in a common framework to investigate Carbon Dioxide Removal (CDR) or Negative Emissions
Modelling the Earth System Response to Negative Emissions
CDR Efficiency: Direct Air Capture
Difference between GROSS and NET CDR
Earth System Reversibility
Other methods
Need to get Serious….
• <1980s – Nuclear
•1990s – Carbon Capture and Storage
•2000s – Bioenergy
•2010s – Bioenergy + Carbon Capture and Storage = BECCS
•2020s – Direct CO2 Removal
The GREAT Climate Solutions
Foresighting & Modelling
Lenton, Boyd et al, NCC 2019Science, Social License & Governance
Emmerson, in prep
Earth System Reversibility
Lenton et al, 2017