CCRN Year 3 Results and Update on Progress Summer Storms and Convective Precipitation

Transcription

1 CCRN Year 3 Results and Update on Progress Summer Storms and Convective Precipitation John Hanesiak Department of Environment & Geography Centre for Earth Observation Science (CEOS) Faculty of Environment, Earth & Resources University of Manitoba

2 Outline Ongoing downscaling of NARCCAP data using HAILCAST future hail, severe storm and convective precipitation research Nocturnal storms/precipitation PECAN and Prairie work Year 4 Plans

3 NARCCAP-Hailcast Project Collaboration between U Manitoba, Applied Environmental Prediction Science (J. Brimelow) and Cloud Physics and Severe Weather Research Section (W. Burrows) of Environment Canada NARCCAP : North American Regional Climate Change Assessment Program Objective: Assess changes in future hail, severe storms and convective rainfall using latest RCMs in conjunction with a cloud / hail model (HAILCAST)

4 Identified 3 well-behaved AOGCM-RCM pairings HadCM3-MM5; HadCM3-HRM3 and CCSM3-MM and SRES A2 ~50 km grid; ~5000 points 18, 21, 00 and 03 UTC 1 March to 30 September ~ 1 billion profiles Identified largest hailstone for each day from HAILCAST Aggregated exceedances (e.g., D > 2 cm) by month, season and year for each of 14 ecozones

5 Identified 3 well-behaved AOGCM-RCM pairings HadCM3-MM5; HadCM3-HRM3 and CCSM3-MM and SRES A2 ~50 km grid; ~5000 points 18, 21, 00 and 03 UTC 1 March to 30 September ~ 1 billion profiles Identified largest hailstone for each day from HAILCAST Aggregated exceedances (e.g., D > 2 cm) by month, season and year for each of 14 ecozones

6 Hail Day Change

7 % Severe Day Change

8

9

10

11 Why the Changes in the Cdn West/NW? Warmer Tsfc and more moisture => larger CAPE, greater max. in-cloud liquid water and max. updraft velocity, deeper clouds and ultimately larger hail. Where CIN is weaker, more hail events and vice versa. Wind shear changes are small over Prairies and western/nw Canada, even slight increases when hail occurs different than U.S. studies. These are preliminary!

12 Summary First study to explicitly model response of hail to warming A significant advance over previous methods Running HAILCAST using dynamic downscaling seems feasible Response of hail to warming varies by region and by season Dramatic decrease in hail potential over east and southeast Fewer hail days expected in the future over most areas, but increase in the portion of severe hail days and median hail diameter => greater hail damage potential Increase in hail damage potential over most areas in MAM, and over higher latitudes and mountains in JJA Changes in W/NW Canada seem to be due to warmer temperatures and more moisture, leading to increases in storm environment parameters. Little change in wind shear.

13 Acknowledgements CCRN NSERC Discovery Grant (Hanesiak) Seth McGinnis from NCAR for extracting/sending the data Al Pankratz for writing some of the code Scott Kehler for writing some of the code Neil Taylor for insightful and helpful discussions Jennifer Bruneau

14 Nocturnal Storms/Precipitation Little is known about nocturnal elevated convection initiation (ECI) and storm processes Huge contributor to annual rainfall Field project based in Kansas Large armada of instrumentation Many academic and government collaborators (e.g NSSL, NASA, NOAA, NCAR)

15 Project Foci Ziolkowski: BL waves and associated ECI (failure as well) Do we see such activity on the Prairies? How well do models handle this? (HRDPS and RDPS) Kehler: Isentropic lift and no apparent forcing associated with ECI High-resolution WRF runs & operational runs (HRDPS and RDPS) Canadian cases for comparisons

16 Example of BL Waves UTC June 8th, 2015

17 km from front

18 UTC

19 Acknowledgements - CCRN, especially Bruce Davison, Branko Zdravkovic and Daniel Princz - NSERC Discovery Grant (Hanesiak) - Canada Foundation for Innovation (CFI) - NSERC-PGS (Kehler) and UMGF (Ziolkowski) - Prairie and Arctic Storm Prediction Centre (PASPC) - PECAN team, especially Tammy Weckwerth (NCAR) and Dave Turner (NSSL)

20 Year 4 Plans Continue with NARCCAP-Hailcast Future Changes Jennifer Bruneau Focus will be on severe weather metrics, convective precipitation & flow patterns Continue PECAN/Prairie nocturnal storms analysis BL wave influences on ECI (Kyle Ziolkowski) Isentropic lift and apparent lack of forcing cases of ECI as well as storm evolution (Scott Kehler) Both above will allow us to better understand nocturnal convective storm processes; huge impact on water issues PECAN case studies and Canadian event (including model) comparisons & transferability of knowledge