Alpine Summer Surface Temperature Amplification Is Spatially Heterogeneous and Intensified by Wind and Sun.

Area of Science:

• Alpine ecology
• Climate science
• Microclimatology

Background:

• Alpine microtopography may buffer climate warming by creating diverse local climates.
• Understanding surface temperature variations is crucial for alpine ecosystem resilience.

Purpose of the Study:

• To quantify differences between alpine surface and free-air temperatures.
• To assess diurnal temperature variations across small spatial scales in alpine plots.
• To compare temperature patterns in open vs. krummholz-covered alpine areas.

Main Methods:

• Thermocouple measurements of surface and 2-m free-air temperatures.
• Paired open and krummholz alpine plots (8x8m) were used.
• Data collected during summer at Cardinal Divide, Alberta, Canada.

Main Results:

• Open alpine plots showed significant surface temperature amplification (avg. 5.6°C higher than free-air).
• Krummholz plots had reduced surface amplification (avg. 4.4°C higher than free-air).
• Surface temperatures varied up to 21°C higher than free-air under high wind and solar radiation; diurnal ranges differed by up to 9.9°C within plots.

Conclusions:

• Standard 2-m free-air temperature data is a mismatch for alpine plant climate models.
• Alpine microclimate variability offers potential refugia from climate warming.
• Further research into alpine surface climate models is needed to assess warming risks and identify refugia.