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Great Lakes Ice Model (GLIM): Developing Great Lakes Ice Model (GLIM) in Lake Erie using the CIOM (Coupled Ice-Ocean Model) . Jia Wang (NOAA GLERL) George Leshkevich, David Schwab, Ann Clites ( NOAA GLERL ) Haoguo Hu, Dima Beletsky ( CILER, UoMich ),
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Great Lakes Ice Model (GLIM):Developing Great Lakes Ice Model (GLIM) in Lake Erie using the CIOM (Coupled Ice-Ocean Model) Jia Wang (NOAA GLERL) George Leshkevich, David Schwab, Ann Clites (NOAA GLERL) Haoguo Hu, Dima Beletsky (CILER, UoMich), Sponsors: NOAA, GLERL with help of USCG
MotivationNeeds for prediction of lake ice using numerical models • No a single climate pattern (PNA, NAO/AO) influencing the GL is dominating, so the predictability of sea ice based on climate pattern indices is poor (Assel and Rodionov 2001, 2002) • Sediment resuspension and transport during winter storm and lake ice season (Schwab et al. 2006, Hawley et al. 2006); Lake Circulation Studies and the Great Lakes Coastal Forecast System (GLCFS) (Schwab) —Need lake ice coupled to an hydrodynamic-sediment model • Biogeochemical/ecosystems modeling such as hypoxia—Multiple stressors (Chen et al. 2004) —Need hydrodynamic-ice circulation model • Regional climate model in the Great Lakes (Lofgren 2005) —Need lake ice model to predict radiation/nergy balance/feedback to the atmosphere, and lake water level (Assel, Quinn&Sellinger 2004) • Great Lakes as a platform for INTERDISCIPLINARY research in a “mini climate system”: Atmosphere, hydrosphere (hydrodynamics, lake ice, biosphere, and lithosphere (land processes, hydrology, coastal erosion) —Need lake ice component
Natural Climate Teleconnection PatternsSea/lake ice as indicator of climate changes: NAO/AO, ENSO/ PNA/PDO? Which is statistically significant? Hudson Bay: Wang et al. (1994a,b; 1995)—ENSO and NAO: 1953-91 Mysak et al (1996)—NAO&ENSO:72/73; 82/83; 91/92 Arctic Ocean: Wang and Ikeda (2000)—AO&ASIO Wang and Ikeda (2001) —Regional and seasonal persp. Wang et al. (2005) —Arctic climate feedback loop Great Lakes: Assel (1998)—ENSO Assel et al. (2003)—Recent trends Rodionov and Assel (2003)—Winter severity
Great Lakes Ice Cover during two extreme climate patterns March 15, 1992: NAO+& SO- (El Nino) March 15, 2001: NAO-&SO+ (La Nino) PNA+ PNA-
There were 13 winters with anomalous high ice cover( > mean+0.7*STD=69.4) 19631967 19721977197819791981 19821985 1986 19941996 2003 (blue are –AO yrs) And also 13 winters with anomalous low Ice Cover (< mean-0.7*STD=40.01) 1964 1966 196919761983 1987 1995 19981999 2000 2001 2002 2006 (Yellow are El Nino yrs) We found -AO signal in the high ice cover winters and El Nino signal in the low ice cover winters
GLIM in Lake Eriebased on CIOM (Wang et al. 2002, 05, 08) 1. POM (Mellor 2000) 2. Multicategory sea ice model (Yao et al., 2000; Wang et al. 2002, 2005, 2008) based on: two-layer ice thermodynamics with 1-layer snow, ice dynamics with viscous-plastic rheology 3. 2-km in Lake Erie similar to Schwab’s GLOFS 4. 22 vertical sigma layers. 5. Daily atmospheric forcing from NCEP/NCAR daily forcing fields (air temperature and humidity at 2m, wind at 10m),solar radiation and air longwave radiation 6. Initial (T/S) fields from measurements
a) 1/9 b) 1/16 c) 1/23 d) 1/30 e) 2/27 f) 3/12 Fig. 6
2008 Feb-27 GLERL-USCG Ice Thickness Measurement Stations 0cm 0 cm 0cm 10 cm 0cm 25cm 15cm 20cm 15 cm 25cm 18cm 20 cm 9cm
a-2) 12/22 a-1) 12/31 a) 1/9 b) 1/16 c) 1/23 d) 1/30 e) 2/27 f) 3/12 g) 3/28 h) 4/6 Fig. 7
Model-data comparison Stations 45005, 45132, and 45142 are shown on the map, but not in the table. These are meteorological stations maintained by either the National Bata Buoy Center (45005) or by Environment Canada (45132 and 45142). ( + NDBC Eastern Great Lakes Marine Data web page)
GLIM model simulation From Dima Beletsky
Toward A Forecast System Hourly forcing in 2004/05
Simulated ice thickness+ice velocity, inserted by wind velocity
Summary • Lake ice seasonal cycles are successfully reproduced, but needs for solid validation of GLIM, plan for 2004-05 ice season (IFYLE obs.), and 2007-08 season (ice thickness obs.) using hourly atmospheric forcing • Model-model intercomparison shows GLIM lake-hydrodynamic model can reproduce similar results to the GLOFS Future efforts: • Transformed GLIM to GLERL (Schwab) GLOFS • Expanded to other Lakes • Applied to Interannual variability of lake ice in Lake Erie • Applied to ecosystem modeling