Extension Climate Science Team

1. Extension Climate Science Team Brad Bauer – MSU Extension Gallatin County / Climate Team

2. Climate Science state.climatologist@umontana.edu

3. Montana Climate Office Kelsey Jencso State Climatologist Mike Sweet Information Services Nick Silverman Hydroclimatologist Kevin Hyde Mesonet Director

4. What is climate? • Climate is the average weather patterns for a region over many years. Variability Climate Variable Average 20 30 10 Years

5. Climate Weather

6. Climate variables Sea-surface temperature Greenhouse gases Snow and ice Land cover Soil moisture Etc………. • Temperature • Precipitation Wind Pressure Solar radiation Humidity The World Meteorological Organization (WMO) defines 50 essential climate variables

7. More Climate Basics

8. Climate Science

9. Kalsta ranch journals, dating back to the 1880s, note everything from late frost that “took a nip off the alfalfa,” to river levels. Sarah Jane Keller Localized climate records • Ranch records • Weather Stations • Proxy records – journals, tree rings Sarah Jane Keller

10. Weather Stations

11. Weather Stations

12. Montana Temperature (1950-2015) • Between 1950 – 2015: • Average annual temperature has increased by 0.42⁰F per decade over the last 65 years. This is an overall increase of 2.7⁰F over this time. • US annual average has increased at a rate of 0.26⁰F per decate since 1950

13. Montana Temperature (1950-2015) • Between 1950 – 2015: • Annual Maximum and Annual Minimum have increased over this time period 0.3⁰F - 0.6⁰F per decade • Winter and springs have warmed the most • Montana’s growing seasons are 11 days longer

14. Montana Precipitation • Our current aveage annual precipitaiton is 18.7 inches • Between 1950 – 2015: • Statewide, the amount of average annual precipitation has shown no statistically significant trend over the past 65 years

15. Montana Precipitation (1950-2015) Spring Precipitation Eastern MT Increases Winter Precipitation North western and central MT decrease No changes in summer and fall

16. Climate Variability Climate Variable Average 20 30 10 Years

17. Climate Change Variability Average Climate Variable 20 30 10 Years

18. Montana Climate Projections • 20 different models make up the ensemble • This gives us a range of projections • Downscaled 4km resolution using statistical downscaling but aggregated to the Climate Division • Two RCP scenarios (4.5 and 8.5) • Comparison of mid- and end-of-century time periods • Historical (1971—2000) • Mid-century (2040—2069) • End-of-century (2070—2099)

19. Change Avg. Annual Temperature (oF) Mid-Century RCP 8.5

20. Change in # of Days Above 90 oF Mid-Century RCP 8.5

21. Change in # of Freeze Free Days Mid-Century RCP 8.5

22. Change in Monthly Avg. Temp. (oF) Mid-Century RCP 8.5

23. Change Avg. Annual Precipitation (%) Mid-Century RCP 8.5

24. Change in # of Days Above 1.0” Mid-Century RCP 8.5

25. Change in # of Consecutive Dry Days Mid-Century RCP 8.5

26. Provisional Summary of Climate Projections For Montana – By 2050 • Temperature hasincreasedhistorically and is projected to increase by another 4-6 oFby mid-century. • Precipitation has stayed about the samehistorically but is projected to increase by around 6-10 %by mid-century. • Drought metrics (i.e. consecutive dry days) are not projected tochange much but are highly uncertain. • Similar future climates are located both closeandfaraway

27. What does it mean for water?

28. Montana Water Trends & Projections Between 1950-2015: • Snowpack has declined, especially since 1980s. • Earlier spring runoff. • Streamflow is influenced by warming & climate variability (e.g., El Nino). Future: • Snowpack will continue to decline with earlier snowmelt. • Streamflow may increase, esp. in spring/early summer. • Late-summer water availability will decrease. • Droughts will be exacerbated by warming. • Demands for groundwater will increase.

29. Brad Bauerbrad.bauer@montana.edu406-582-3283 http://msuextension.org/climate/