Iowa Climate Statement 2014

Christopher J. AndersonResearch Assistant Professor, Department of Agronomy

Assistant Director, Climate Science Program

Iowa State University

Ames, IA 50011

23 October 2014

Climate Change in Iowa is different from Climate Change on TV

Source: Min et al (2011, Nature). Human contribution to more-intense precipitation extremes.

The pattern of change in extreme rainfall is a fingerprint of human influence on climate change.

2013

2014

2012

2010

2008

Rare Spring-Summer

rainfall combinations

are no longer rare.

1893-1980: 7

2008-2014: 5

Dry SpringDry Summer

Dry SpringWet Summer

Wet SpringWet Summer

Wet SpringWet Summer

Source: Bindoff, N.L., P.A. Stott, K.M. AchutaRao, M.R. Allen, N. Gillett, D. Gutzler, K. Hansingo, G. Hegerl, Y. Hu, S. Jain, I.I. Mokhov, J. Overland, J. Perlwitz, R. Sebbari and X. Zhang, 2013: Detection and Attribution of Climate Change: from Global to Regional. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 867–952, doi:10.1017/CBO9781107415324.022.

Two human climate change fingerprints on temperature:(1) Land has warmed more than ocean(2) Northern latitude has warmed more than middle latitude

Source: Union of Concerned Scientists, Heat in the Heartland: 60 years of warming in the Midwest (2012)

Summer heat wave

trend is determined by

source of air.

Iowa’s hottest summers

are dry tropical, moist

tropical, and moist

tropical+.

Warming of northern

latitude has affected dry

polar, dry moderate,

moist polar, moist

moderate, but not Iowa’s

hottest air masses.

Source: Union of Concerned Scientists, Heat in the Heartland: 60 years of warming in the Midwest (2012)

Iowa City June-July-August Minimum Temperature

Humidity increase causes more hot nights during summer.

In Iowa City, high summer night time temperature is more frequent. Ten of the top 15 years have occurred since 1990.

Iowa City 3-day Minimum Temperature

Humidity increases causes more hot nightsduring summer heat waves.

Maximum of 3-day Minimum Minimum of 3-day Minimum

Length of Growing Season is 10 days longer across the Midwest

In Iowa, corn is planted one week earlier than in the 1950s.

As climate changes there will be more wet springs

A one-in-ten year wet spring during 1960-1999 becomes a two-in-five year wet spring during 2020-2059.

Data Source: Climate projections from Stoner et al. (2013)

Climate Projection of Iowa May-June Rainfall

1960-1999 2020-2059

As climate changes there will more hot summer nights

Data Source: Climate Projections from Stoner et al. (2013)

Number of July Nights with Temperature > 70F

1960-1999 2020-2059

As climate changes there will be more hot summer days

Number of July Days with Temperature > 95F

2013: an example of things to come

2013

Data Source: Stoner et al. (2013)

What might Iowa Educators do Next?

• Identify additional climate-health connections

• Develop monitoring and decision tools

• Produce Information Sheets similar to Union of Concerned Scientists “Confronting Climate Change” series

Iowa Climate Statement 2014

Christopher J. AndersonResearch Assistant Professor, Department of Agronomy

Assistant Director, Climate Science Program

Iowa State University

Ames, IA 50011

23 October 2014

2013

2013: an example of things to come

Source: Bindoff, N.L., P.A. Stott, K.M. AchutaRao, M.R. Allen, N. Gillett, D. Gutzler, K. Hansingo, G. Hegerl, Y. Hu, S. Jain, I.I. Mokhov, J. Overland, J. Perlwitz, R. Sebbari and X. Zhang, 2013: Detection and Attribution of Climate Change: from Global to Regional. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 867–952, doi:10.1017/CBO9781107415324.022.

The pattern of change in extreme rainfall is a fingerprint of human influence on climate change.

Temperature trend can not be explained withoutHuman emissions of greenhouse gases

Ocean Has Absorbed 64% of Energy added by Greenhouse Gas Increase

More complete measurements, such as satellites since 1980, has reduced substantially the uncertainty in energy storage estimates.

Source: climatechange2013.org

Source: Union of Concerned Scientists, Heat in the Heartland: 60 years of warming in the Midwest (2012)

Des Moines June-July-August Air Masses

Average Maximum Temperature

Upward change since 1945

Downward change since 1945

Dry Tropical: 95OF, -1.0OF

Moist Tropical+: 94OF, +2.0OF

Moist Tropical: 88.5OF, +0.5OF

Dry Moderate: 84.5OF, -0.25OF

Moist Moderate: 84OF, +4.0OF

Dry Polar: 77.5OF, +2.5OF

Moist Polar: 76OF, +6.0OF

Supporting Slides for Historical NarrativeMaximum of 3-day Average and Max Temp

Dots: Values for each yearRed Line: 90%-tileBlue Line: 10%-tileBlack Line: 1981-2010 average