On the measurement of microclimate

Many organisms live in environments which temperatures differ substantially from those measured by standard weather stations. The last decade has witnessed a paradigm shift efforts to quantify these differences and understand their ecological, functional evolutionary implications. This renewed interest microclimate ecology been accompanied the development of various compact temperature sensors radiation shields. However, it is clear that there are many pitfalls when measuring using devices. Here we address problem microenvironments accurately. We first discuss theory surface, ground air with reference energy fluxes how modified material, reflective properties size device. highlight particular difficulties associated temperature. then report on results series experiments recorded commonly used loggers compared obtained research-grade instruments synoptic While accurate measurements surface at night shaded can be relatively easily obtained, show substantial errors expected exposed sunlight. Most yield large errors, reach 25°C due radiative operating thermometer. cannot wholly overcome shielding thermometer sunlight, as shield itself will influence both being accuracy measurement. demonstrate reasonably estimates low-cost unshielded ultrafine-wire thermocouples possess low thermal emissivity highly surface. As processes create microclimatic variation same cause other logger types should care, generally avoided sunlight close where wind speeds lower. urge researchers interested microclimates effects pay greater heed physics heat exchange attempting measure trade-offs exist doing so.