Arctic Issues and Planned AMAP Assessments

Transcription

1 Arctic Issues and Planned AMAP Assessments Kaarle Kupiainen*, Andreas Stohl, Mark Flanner Co-leads of the AMAP SLCF Expert Group *Senior Research Scientist, Ph.D. Finnish Environment Institute (SYKE) Acknowledgements: Experts of the AMAP 2015 and 2021 SLCF assessment groups

2 Climate Acidification Radioactivity POPs and heavy metals SLCFs/SLCPs, i.e. methane, black carbon, tropospheric ozone to monitor and assess the status of the Arctic region with respect to pollution and climate change issues. to produce sound science-based, policy-relevant assessments and public outreach products to inform policy and decision-making processes. 2

3 Arctic Council and air pollution Ensimmäinen taso toinen taso kolmas taso EGBCM Expert Group on Black Carbon and Methane 4

4 AMAP SLCF 2015 assessment Scientific assessment with a direct policy connection within the Arctic Council Review of scientific literature and own modelling work Arctic (Council) focus (source regions, climate impacts) Scientific peer review process organized by AMAP

5 Global Climate Model approach to calculating the radiative forcing by SLCFs and associated climate response Quantification of Arctic equilibrium warming due to: Current emissions and ECLIPSE maximum global SLCF reductions 6 regions, Rest of World (ROW), and latitude bands 7 emission source sectors Multi-specie approach: BC, OC, SO2, and nmops Also review of Arctic observations (concentrations and trends of pollutants) with observation-model comparisons

6 Regions outside of the Arctic are important contributors to the annual mean burden of BC (in Mg) in the Arctic. There is significant spread between the model results Arctic BC burden (Mg) Gas 0 United States Canada Russia Nordic Countries Rest of Europe East and South Asia Rest of World NorESM CESM SMHI-MATCH CanAM Emissions (2010 situation) from East+South Asia and Russia are the largest contributors to BC burdens in the Arctic in all the models, with mean contributions of 43% and 21%, respectively. The Nordic countries contribute less to Arctic BC burdens than any other region, in accordance with lower emissions.

7 A multi-pollutant approach is important to estimate Arctic equilibrium surface temperature response due to forcing for each sector and source region by BC, OC, SO4, and O3 (nmops) (averaged over all models) The largest contributions to warming in the Arctic come from East+South Asian domestic emissions, Russian fires and flaring emissions, and domestic and fire emissions from the rest-of-world.

8 The Arctic response is a results of both radiative forcing within the Arctic (solid fill) as well as from extra-arctic (pattern fill) contribution. Heat transport is an important pathway of the response. The Arctic climate is coupled with lower latitudes. Importance of heat transport Figure: Arctic equilibrium surface temperature response to all emissions from each source region due to direct forcing by BC, OC, SO 4 and O 3 (nmops) averaged over four models.

9 High latitude emissions have the highest surface temperature response per unit emission Nordic Countries Arctic equilibrium surface temperature response per unit emission to source sectors within each region

10 What is the Arctic surface temperature response to mitigation of SLCFs? Current legislation scenario (BASELINE) and maximum technically feasible global reductions in emissions of black carbon, methane, and non-methane ozone precursors (MITIGATE) Global annual-mean emissions applied in the BASELINE and MITIGATE transient simulations BASELINE MITIGATE

11 Reduced warming in the Arctic in response to the ECLIPSE mitigation scenario (Regional Temperature Potential Coefficient (RTP)-based estimate). Sum over all sectors and regions. Indirect effects not included. Results of two models. BC (snow) BC (atm) CH average Net: -0.40K BC: -0.23K CH4: -0.17K

12 Reduced warming in the Arctic in response to the ECLIPSE mitigation scenario (Regional Temperature Potential Coefficient (RTP)-based estimate). Sum over all sectors and regions. Including indirect cloud effects Co-emitted OC Reduced Arctic warming (K) BC (atm) BC (snow) OC SO2 NOx VOC BC (snow) BC (atm) CH4 CO CH4 Net -0.50

13 What is the transient response to a drastic mitigation of SLCFs? Application of CESM model with fully coupled atmosphere, ocean, land, and sea-ice components, initialized to year 2001 conditions. Simulations were carried out to 2050 with 4 ensemble members representing a current legislation scenario (BASELINE) and 4 ensemble members representing maximum technically feasible global reductions in emissions of black carbon, methane, and non-methane ozone precursors (MITIGATE)

14 Diagnosed climate impact from transient simulations including cloud indirect effects Differences in the ensemble-mean climate states (MITIGATE BASELINE) averaged over Changes significant at p=0.05 are shown in bold. a Includes change from aerosols (BC, OC, and dust) deposited to land snow b Includes change from aerosols (BC, OC, and dust) deposited to land snow Cloud changes offset the benefit associated with direct forcing. Cloud indirect effects vary substantially between models

15 AMAP SLCF 2021 assessment Group of ~50 scientists from 15 countries (AC and observers) Emission inventory/scenario analyses, multi-species approach Anthropogenic and natural emissions; review of emission inventories; Scenarios: SLCFs in the context of GHG policies (i.e. IEA WEO2017) Costs of mitigation Arctic observations - trends and concentrations: atmosphere, snow samples, ice cores, lake sediments; Modelling of climate impacts (CMIP6, own modellings); Co-effects on human health and ecosystems Reducing uncertainties; model-observation comparisons; gaps identified in/after AMAP (2015) BC/O3 and CH4 assessments; etc.

16 Collaborative work Within the Arctic Council: collaboration with EGBCM (policy), ACAP (demonstrations), Linkages to International Organizations: CLRTAP Centers, WGs and TFs; options for joint assessment work with CLRTAP in 2021? Other UN organizations: UNFCCC, IPCC, WMO, IMO OECD Climate and Clean Air Coalition (CCAC) Science initiatives: IGAC activity - Air Pollution in the Arctic. Climate, Environment and Societies (PACES) European Commission Black Carbon in the Arctic Action

17 Thank you! Kaarle Kupiainen