Summertime cyclones over the Great Lakes Storm Track from 1860–2100: variability, trends, and association with ozone pollution

摘要: Abstract. Prior work indicates that the frequency of summertime mid-latitude cyclones tracking across Great Lakes Storm Track (GLST, bounded by: 70° W, 90° 40° N, and 50° N) are strongly anticorrelated with ozone (O3) pollution episodes over Northeastern United States (US). We apply MAP Climatology Mid-latitude Storminess (MCMS) algorithm to 6-hourly sea level pressure fields from 2500 yr simulations GFDL CM3 global coupled chemistry-climate model. These include (1) 875 constant 1860 emissions forcings (Pre-industrial Control), (2) five ensemble members for 1860–2005 (Historical), (3) future (2006–2100) scenarios following Representative Concentration Pathways (RCP 4.5 RCP 8.5) a sensitivity simulation isolate role climate warming changes in O3 precursor 4.5*). The Historical capture mean variability traversing GLST within range determined four reanalysis datasets. Over 21st century (2006–2100), decreases under 8.5 scenario mean. trends significant when assessed relative Pre-industrial Control simulation. In addition, 4.5* enables us determine relationship between high-O3 events (> 95th percentile) absence emission changes. cyclone explains less than 10% US model, implying other factors play an equally important determining events.