Source attribution of climate and health impacts from aerosols

Transcription

1 Source attribution of climate and health impacts from aerosols Daven Henze, Forrest Lacey, Luke Reed (CU Boulder) Harry Vallack, Johan Kuylenstierna (SEI, University of York) Colin Lee, Randall Martin (Dalhousie University) Erika Sasser (US EPA), Susan Anenberg Support from NASA Applied Sciences and CCAC

2 Climate and health impacts of Short Lived Climate Pollutants (SLCPs) SLCPs = CH 4, BC, OC, CO, VOCs, NO x, SO 2, NH 3, (HFCs) Ramanathan and Xu, PNAS, 2010; Hu et al., Nature CC, 2013 Ramanathan and Carmichael, Nature Geo, 2008 UNEP 2011; Shindell et al., Science, 2012

3 Adjoint modeling for source-receptor analysis: Forward Model (source-oriented) Sensitivity of all model concentrations to one model source Adjoint Model (receptor-oriented) Sensitivity of model concentration in specific location to many model sources Concentration at the receptor Forward Perturbation at source region t 0 t n Changes of concentration t n adjoint area of possible origin t 0

4 Adjoint modeling for source-receptor analysis: Forward Model (source-oriented) Adjoint Model (receptor-oriented) Sensitivity of all model concentrations to one model source Sensitivity of model response over a region to many model sources example responses: radiative forcing, population weighted concentration, Response metric at the receptor Forward Perturbation at source region t 0 t n Changes of concentration t n cost scales with # of sources adjoint area of possible origin t 0 cost scales with # of responses

5 Source attribution of aerosol climate impacts Abundance-based RF AR4, Forster et al., 2007 Emissions-based T High resolution source attribution with GEOS-Chem adjoint model: - direct aerosol radiative forcing (Henze et al., 2012) - indirect, semi-direct, and snow/ice albedo (UNEP, 2012; Shindell et al., 2012) - equilibrium and transient latitudinal temperature response (Shindell, 2012) - incorporated into decision support tools (GLIMPSE, Akhtar et al., 2013; CCAC SNAP toolkit)

6 Country Level Contribution to Global Average T due to Removal of Biofuel Emissions 2 mk Climate Effects are a function of: Radiative Forcing Efficiencies Total Carbonaceous Biofuel Emissions BC/OC Emissions Ratio for Biofuel Emissions -2 mk

7 Decision Support for Global Initiatives Climate and Clean Air Coalition (UN) - Reducing BC, CH 4 and other emissions from vehicles, brick production, oil & gas, solid waste Cross-cutting efforts: - Financing SLCP mitigation - SLCP National Action Plans First action: rapid emission and scenario assessment toolkit Mitigation Emissions Response O 3, PM 2.5 CH 4 Impacts - health - climate - ecosystem Use country-specific responses for arbitrary emissions from adjoint calculations

8 Source attribution of aerosol health impacts Sensitivity of Bangladesh annual pop-pm 2.5 to emissions: SO 2 BC

9 Source attribution of aerosol health impacts Sensitivity of Bangladesh annual pop-pm 2.5 to emissions: SO 2 BC Response to global emissions 1.00 µg/m Owing to E in Bangladesh (81,686 deaths) Owing to E in Rest of World (92,830 deaths) SO2 NOx BC OC NOx BC OC fossil fuel biofuel

10 Source attribution of aerosol health impacts Sensitivity of Bangladesh annual pop-pm 2.5 to emissions: SO 2 BC Response to global emissions 1.00 µg/m Owing to E in Bangladesh (81,686 deaths) Owing to E in Rest of World (92,830 deaths) SO2 NOx BC OC NOx BC OC fossil fuel biofuel Apply maximum controls: 36,867 deaths from E in Bangladesh 62,853 deaths from E in Rest of World

11 Source attribution of PM 2.5 related mortality throughout the globe Previous works have investigated large-scale impacts: - global reductions to fossil and biofuel (Jacobson, 2010) - global BC and CH4 measures (Anenberg et al., 2011; 2012) - widespread adoption of vehicle standards (Shindell, 2011) However, coarse models have trouble estimating exposure: Dust SO 4 NH 4 PM 2.5 NO 3 CMAQ (Punger & West, 2013) GEOS-Chem (Li et al., submitted) Grid Resolution (degrees) OC BC Individual components of PM 2.5 underestimated by 5-40% in a 2 x2.5 simulation over the US. Impacts of resolution not globally heterogeneous.

12 Source attribution of PM 2.5 related global mortality PM 2.5 subgrid variability (0.1 x 0.1 ) resolved using MODIS AOD and CALIOP vertical profile (van Donkelaar et al., 2013): 2 x2.5 grid cell Satellite-derived PM 2.5 [µg/m3] In situ PM 2.5 [µg/m3] Satellite-derived PM 2.5 shows good agreement with in situ total PM 2.5 and speciated PM 2.5 concentrations (Philip et al., 2014).

13 Source attribution of PM 2.5 related global mortality PM 2.5 subgrid variability (0.1 x 0.1 ) resolved using MODIS AOD and CALIOP vertical profile (van Donkelaar et al., 2013): This dataset used to drive GEOS-Chem adjoint simulations: SO 2 BC M global for 10% reduction to emissions in any grid. (Lee et al., submitted)

14 Source attribution of PM 2.5 related national mortality Satellite-based exposure estimate with GEOS-Chem adjoint source apportionment: fossil fuel sources Peru Bolivia Luke Reed, CU Boulder Contribute to CCAC Latin America Assessment and SNAP Toolkit

15 Cookstove intervention: health impacts Top 5 countries for eliminating emissions from 1 million cookstoves: Forrest Lacey, CU Boulder Pop-weighted global PM 2.5 [ng/m3] 4 Nepal 3 Bangladesh ng m -3 reduction Brazil Romania India 0.3 mk cooling Global mean land T [mk]

16 Cookstove intervention: climate impacts Top 5 countries for eliminating emissions from 1 million cookstoves: Pop-weighted global PM 2.5 [ng/m3] Global mean land T [mk] 3 Romania Uzbekistan Tajikistan China Burkina Faso Forrest Lacey, CU Boulder ng m -3 reduction 1.4 mk cooling

17 Cookstove intervention: combined climate and health impacts Top 5 countries for eliminating emissions from 1 million cookstoves: Pop-weighted global PM 2.5 [ng/m3] Global mean land T [mk] 3 2 Romania Nepal Uzbekistan China Bangladesh Forrest Lacey, CU Boulder ng m -3 reduction 1.1 mk cooling

18 Final Comments NASA earth system models (GEOS-Chem, GISS) used to estimate health and climate impacts of aerosols. Adjoint modeling provides source-receptor relationships at scales of interest for national and international decisionsupport tools: GLIMPSE, CCAC, HTAP. Remote sensing data (AOD) improves exposure estimates in global models. Results for different response metrics (health, climate, ) can be combined for co-benefits studies. Additional response metrics (e.g., ecosystem impacts of O 3 and N deposition) considered in other AQAST Tiger Team activities (Lapina et al., 2014; Lee et al., in prep; Davis et al., in prep)

19 Climate and health impacts of Short Lived Climate Pollutants (SLCPs) SLCPs = CH 4, BC, OC, CO, VOCs, NO x, SO 2, NH 3, (HFCs) Ramanathan and Xu, PNAS, 2010; Hu et al., Nature CC, 2013 Ramanathan and Carmichael, Nature Geo, 2008 UNEP 2011; Shindell et al., Science, 2012

20 Using regional climate sensitivities: impacts of present day fossil fuel BC emissions on NH mid T surf T C = K K Shindell 2012: parameterized NH mid latitude land temperature response [ K / (W/m2)] x10-5 mw/m 2 5 mw/m 2 GEOS-Chem adjoint: drf j /de i Sensitivity of RF in latitude band J to emission in any location i.

21 Using regional climate sensitivities: impacts of present day fossil fuel BC emissions on NH mid T surf T C = K K = 0.54 K Compare to using global RF and clim response: x K K = 0.27 K -5 mw/m 2 5 mw/m 2

22 Climate and Clean Air Coalition (CCAC) - Initiated Feb Bangladesh, Colombia, Ghana, Mexico, Sweden, US, and UNEP - now 61 members (39 countries, European Commission, multiple NGOs). - US involvement through the State Department and EPA. - SLCP Task Force Bill introduced to Congress (May 20, 2013). Objectives - Raising awareness of SLCP impacts and mitigation strategies - Enhancing and developing new national and regional actions - Promoting best practices and showcasing successful efforts - Improving scientific understanding of SLCP impacts & mitigation strategies

23 Radiative Forcing Sensitivities Sensitivities from every sector and region: Calculated very efficiently using GEOS-Chem adjoint (Henze et al., 2007) and LIDORT (Spurr, 2002)

24 Direct Radiative Forcing efficiencies How does variability in DRF efficiency impact direct forcing of aerosols across changes to various emissions sources and sectors following future scenarios? W m-2 / (kg m-2 yr-1) % change in DFR The change in DRF per change in BC emission % change in BC emissions for RCP 4.5 Henze et al., 2012

25 Refining the bar chart: from abundance-based to emissions-based RF Perturbing emissions & recalculating RF: Sector specific contributions: Fuglestvedt et al., 2008; Sector & regional specific contributions: Unger et al., 2008 Koch et al., 2005; Unger et al., 2010; Shindell et al., 2011; 2012; Menon and Bauer, 2012

26 Impacts of satellite downscaling on NH 3 emissions global mortality response coefficients log 10 ( with downscaling / without) Impacts of resolution can be dramatic, increasing or decreasing, and depend upon environmental condition.

27 Resolution effects on response coefficients: Mexico Contribution of SO 2 emissions per grid-box to Mexico s pop-pm 2.5 : coarse fine fine aggregated Coarse simulation overestimates impacts of emissions near urban center and underestimates in surrounding areas January

28 Resolution effects on response coefficients: Mexico Contribution of SO 2 emissions per grid-box to Mexico s pop-pm 2.5 : coarse fine fine aggregated Total contribution of species to % of Mexico s pop-pm 2.5 : 40% 35% 30% 25% 20% 15% 10% 5% 0% coarse fine aggregated NH3 SO2 BC OC NOx January

29 Importance of highly resolved source regions Spatial heterogeneity in SO 2 emissions changes following - a single Representative Concentration Pathway for AR5 RCP 8.5:

30 Importance of high-resolution emissions-based RF Spatial heterogeneity in SO 2 emissions changes following - a single Representative Concentration Pathway for AR5 - the difference between two Pathways for AR5 RCP 8.5: RCP RCP Significant intra-regional variability