ARSF project GB08 /15: Modelling gap microclimates in broadleaved deciduous forests using remotely sensed data. Led by: Dr. Alan Blackburn, Dept. of Geography, Lancaster University, Lancaster LA1 4YQ. Location: Eaves Wood, Staffordshire, UK.

When treefalls occur or tree crowns are damaged due to windthrow, tree death, disease or anthropogenic disturbance, the gaps that are created in the forest canopy initiate dramatic changes in abiotic conditions, particularly microclimate. It is generally acknowledged that the magnitude of the changes in microclimate is related to the size, shape and 3-D geometry of the gap and characteristics of the remaining surrounding canopy. However, there is currently a paucity of models that are able to describe these relationships, particularly in temperate forests. Furthermore, we currently have very limited ability to characterise the consequences of the variations in the spatial distribution of gaps on the microclimatic conditions across entire forest stands. The proposed project aimed to address these issues by using a unique combination of field observations, numerical modelling and remote sensing techniques. In situ observations at the field site helped to provide the empirical evidence with which to construct a dynamic spatio-temporal model of gap microclimates, while experiments over the next growing season developed robust and extendible remote sensing techniques for characterising relevant gap and canopy properties. This study was only possible because of the unique operational and sensing capabilities of the NERC ARSF, combined with comprehensive validations based on an extensive ground campaign coinciding with the overflights.