CLIMATOLOGY Advancing Adaptation Workshop Dr. Kenneth A. - PowerPoint PPT Presentation

A SNAPSHOT OF MINNESOTA’S CHANGING CLIMATOLOGY Advancing Adaptation Workshop Dr. Kenneth A. Blumenfeld, State Climatology Office January 31, 2017

Three Leading Changes Ongoing and Expected to Continue 1. Minnesota getting warmer and wetter 2. Warming driven by loss of cold, all seasons 3. Heavy rainfall more frequent and intense

Minnesota Average Temperature and Precipitation 35 34 33 32 Cool/wet Warm/wet 31 30 Annual Precipitation (in.) 29 28 27 26 25 24 23 22 21 20 19 18 17 1895-1986 Cool/dry Warm/dry 16 15 35 36 37 38 39 40 41 42 43 44 45 46 Annual Temperature (F)

Minnesota Average Temperature and Precipitation 35 34 2016 33 32 Cool/wet Warm/wet 31 30 Annual Precipitation (in.) 29 28 27 26 25 24 23 22 21 20 19 1997-2016 18 17 1895-1986 Cool/dry Warm/dry 16 15 35 36 37 38 39 40 41 42 43 44 45 46 Annual Temperature (F)

Warming greatest in north, at night (lows), and during winter Total temperature change, 1895-2015 Annual Average Winter Lows Summer Highs

Winter warming 10x faster than summer Avg. change Avg. change Temperature Season per decade per decade Metric since 1895 since 1970 Winter Seasonal Avg. + 0.36°F + 1.00°F (Dec - Feb) Summer Seasonal Avg. + 0.14°F + 0.10°F (Jun - Aug)

Length and Magnitude of 10 F Temperature Season, Duluth MN 4.5 4 Daily Average T Degrees Below 10F 3.5 3 2.5 2 1956-1975 1.5 1 0.5 0

Length and Magnitude of 10 F Temperature Season, Duluth MN 4.5 4 Daily Average T Degrees Below 10F 3.5 3 2.5 1956-1975 2 1976-1995 1.5 1 0.5 0

Length and Magnitude of 10 F Temperature Season, Duluth MN 4.5 4 Daily Average T Degrees Below 10F 3.5 3 2.5 1956-1975 2 1976-1995 1996-2015 1.5 1 0.5 0

Changes in Heavy Precipitation Frequency and Intensity from 40 Long-Term Minnesota Stations, 1916-2015 30% 11 1" rainfall frequency change vs 1916-60 avg 25% 10 10-yr statewide (40-station) maximum 20% Ann. avg statewide (40-station) max (10-yr) Maximum Rainfall (inches) 9 Frequency Difference 15% 8 10% 5% 7 0% 6 -5% 5 -10% -15% 4

Extreme rainfall: “Mega” rain events (6” + over 1000 sq mi) are increasing – June 28-29, 1975, Northwest MN – June 30-July 2, 1978, Southeast MN – July 23-24, 1987, Twin Cities Superstorm – June 9-10, 2002, Northern MN – September 14-15, 2004 Southern MN – August 18-20, 2007, Southern MN – September 22-23, 2010 Southern MN – June 19-20, 2012, Northeast MN – July 11-12, 2016, East-central MN – August 10-11, 2016, Central and Southeast MN

Thank You!