HTAP-2 analysis for the Arctic

Transcription

1 Institute for Climate and Atmospheric Science SCHOOL OF EARTH AND ENVIRONMENT Photo: Chuck Brock, NOAA. HTAP-2 analysis for the Arctic Steve R. Arnold 1, Louisa K. Emmons 2, Kathy S. Law 3, Sarah A. Monks 4,5, + HTAP modelling groups 1. Institute for Climate and Atmospheric Science, University of Leeds. 2. Atmospheric Chemistry Observations and Modeling Division, NCAR, USA. 3. LATMOS / IPSL, Paris. 4. Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, United States. 5. Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, United States. HTAP2 Workshop, Potsdam, 17 th Feb 2016

2 Long-range transport to the Arctic : Based on Figure 5.1 from AMAP, The Impact of Black Carbon on Arctic Climate (2011). By: P.K. Quinn et al. After Stohl (2006). Observations and models both show episodic transport events from mid-latitude source regions and boreal fires to the Arctic. Tough test for global models.!

3 Multi-model analyses for the Arctic HTAP (Shindell et al., 2008) Surface evaluation, mid-latitude source sensitivities. POLMIP (Emmons et al., 2015; Monks et al., 2015; Arnold et al., 2015) Evaluation of vertical profiles, evaluating fire influence, ozone sensitivity to NOy and VOC chemistry. Focus on trace-gases. AMAP / ECLIPSE (AMAP, 2015; Eckhardt et al., 2015; Sand et al., 2015) Evaluation of trace gases and aerosol at surface & in vertical, Arctic T response to local and remote forcing. HTAP II?

4 Model performance in the Arctic - HTAP 1 (Shindell et al., 2008) CO CO O 3 O 3 Models (2000) Multi-annual obs 2000 obs Shindell et al., (2008) Models exhibit large spread in their ability to reproduce observed Arctic pollutant enhancements transport and chemistry both contribute to spread.

5 Model performance in the Arctic CO CO HTAP-2 HTAP-2 O 3 CO O 3 CO Low CO bias persists. Also evident in POLMIP and AMAP assessments.

6 Model performance in the Arctic O 3 O 3 CO HTAP-2 CO HTAP-2 O 3 O 3 Improvement in mean ozone at surface. Large spread at Barrow in spring remains.

7 High latitude ecosystem impacts (O 3 ) CAM-chem ozone source tags + JULES vegetation model simulations (with Sitch et al., ozone vegetation damage parameterisation). ΔNPP (minus Europe O 3 ) ΔNPP (minus Eurasia fire O 3 ) ΔNPP (minus E Asia O 3 ) ΔNPP (minus N America O 3 ) Arnold, Monks, et al., (in prep.) Per kg emitted, NOx emissions from fires produce most vegetation ozone damage.

8 HTAP2 ozone source sensitivities (surface Mar-Apr-May) EU NA EA EU NA EA Surface ozone source sensitivities in Arctic differ between models. Implications for impact assessments. EU NA EA [%]

9 For climate forcing and Arctic import, the vertical profile matters Ozone Black carbon aerosol Ozone radiative effect per ppbv tropospheric O 3 increase (Rap et al., GRL, 2015). Arctic equilibrium temperature response to uniform layers of BC in the Arctic atmosphere located at different altitudes. (Flanner, 2013)

10 Relative source contributions to Arctic vertical profiles Fractional contributions to Arctic concentrations of 25-day lifetime CO tracers. Asian anthro N American anthro European Anthro Asian fire N American fire European fire POLMIP project Monks, S. A., et al., (2015), Atmos. Chem. Phys., 15, , doi: /acp

11 HTAP2 evaluation vs ARCTAS 2008 observations (Spring) Only CAM-Chem and C-IFS are for year Note: monthly model output interpolated to aircraft position. Emmons et al., (2015)

12 HTAP2 evaluation vs ARCTAS 2008 observations (Summer) Only CAM-Chem and C-IFS are for year Note: monthly model output interpolated to aircraft position. Emmons et al., (2015)

13 PAN: an important but uncertain driver of Arctic ozone? Model experiment where all PAN is immediately converted to NO 2 & CH 3 CHO. Sarah Monks. [% change in NOx and ozone]. PAN/CO ratio from AMAP models. AMAP Assessment 2015: Black Carbon and Ozone as Arctic Climate Forcers.

14 HTAP2 PAN source sensitivities European Arctic N American Arctic Asian Arctic

15 HTAP2: Arctic import of PAN vs CO 60-90N Controlled by vertical transport, organic chemistry, heterogeneous chemistry? POLMIP models Arnold et al., (2015) Arctic ozone sensitivity to model PAN range (POLMIP). Arnold et al., (2015)

16 HTAP2 PAN/ CO source sensitivities ~500 hpa Relative sensitivities of PAN / CO to emission perturbations tells us about more than just atmospheric transport. Separate sensitivities to VOC and NOx perturbations?

17 Possible HTAP2 Arctic analyses - Analysis to inform PACES working group on processing during LRT to Arctic. - NOy, aerosol sensitivities to vertical transport, chemical processing,. - Sensitivity of Arctic climate to local and mid-lat SLCP profile perturbations (Stjern et al., CICERO). - Ozone and nutrient deposition impacts at high latitudes. How good are veg models here? - Source-receptor relationships applied to future scenarios for Arctic. Changes in European and Asian influence AQ vs climate. What is available? - Matrix of source perturbation simulations? RBU region? Separate VOC and NOx perturbations? Who / when? Dec 2016 ACP deadline??

18 HTAP2 ozone source sensitivities ~ 500hPa [%]