Microclimate, the hidden driver of species distributions

ongoing

Recent research has increasingly highlighted that species and community distributions are not simply tracking climate change. Indeed, significant delays in species distribution responses, and even unexpected downward or equator-ward shifts have all been observed. Several mechanisms have been proposed to explain these mismatches, such as slow population dynamics, habitat fragmentation or spread-limiting biotic interactions. Yet, the hypothesis forwarded here is that we first need the relevant baseline climate change data before we can accurately answer this question. Indeed, organisms respond to microclimate change, which can be strongly disconnected from macroclimate change. It is the local temperatures near the ground or below the vegetation - often tens of degrees different from weather station data - that set the bounds of organisms’ range limits. In this project, we will take advantage of the SoilTemp-database, a global database of more than 100,000 in-situ measured microclimate time series. I will use it to make global predictions of the rate of microclimate change over time. These new global microclimate data products will then be used to improve field-based estimates of the velocity of plant species’ distribution range shifts. These improved estimates of species’ reactions to climate change are critically needed to adjust biodiversity management to a rapidly changing world.