1. Extension Climate Science Team
And effort to describe past and future climate trends that affect different sectors of the State’s economy
Water, Forestry, and Agriculture
Partnership of MSU and UM through the IoE
A series of listen session across the state for each sector drove the questions that were examined. “What do you need to know about climate change to make decisions that affect you and your operation”
The premise is we need to know the state of knowledge on how climate is changing and how that affects these sectors before we can develop bmp to adapt or migrate to the change.
Brad Bauer – MSU Extension
Gallatin County / Climate Team

2. Climate Science

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 10 20 30
Years

5. Climate Weather

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

7. More Climate Basics

8. Climate Science

9. Localized climate records
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 Station Details Station Name:
LEWISTOWN MUNI AP, MT USA
Element
Start
End
Years
Observations
PRCP:Precipitation (tenths of mm)
2/21/2017
121
43,054
SNOW:Snowfall (mm)
1/22/2017
21,854
TMAX:Maximum temperature (tenths of degrees C)
42,773
TMIN:Minimum temperature (tenths of degrees C)
42,792

11. Weather Stations Station Details Station Name: MSU Element Start Years
Observations
PRCP:Precipitation (tenths of mm)
125
44,606
SNOW:Snowfall (mm)
30,059
TMAX:Maximum temperature (tenths of degrees C)
44,631
TMIN:Minimum temperature (tenths of degrees C)
44,673

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 10 20 30
Years

17. Climate Change
Variability
Average
Climate Variable 10 20 30
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 has increased historically and is projected to increase by another 4-6 oF by mid-century.
Precipitation has stayed about the same historically but is projected to increase by around 6-10 % by mid-century.
Drought metrics (i.e. consecutive dry days) are not projected to change much but are highly uncertain.
Similar future climates are located both close and far away

27. What does it mean for water?
Example ‘lead-in’ slide to each issue – we should have a similar one for forests and agriculture

28. Montana Water Trends & Projections
Between :
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 Bauer brad.bauer@montana.edu 406-582-3283