US Department of Energy Atmospheric Radiation Measurement (ARM) Macquarie Island Clouds and Radiation Experiment (MICRE)

The inadequate representation of clouds and moist convection in climate models is the main limitation in current representations of the climate system. Large biases in shortwave radiation and sea surface temperatures in the Southern Ocean are characteristic of most models.

These biases are due to an incorrect microphysical representation of clouds in models, in particular the ability to simulate sufficient low-level clouds. The ARM (Atmospheric Radiation Measurement) programme was used at Macquarie Island to characterise clouds and their effects on surface energy balance in the high southern latitudes. Instruments used: 1) Surface broadband radiometers measuring sky and ground broadband radiation (incoming and outgoing visible and infrared) 2) Microwave radiometer: brightness temperature in 2 or 3 channels, sensitive to water vapour and liquid water 3) Multi Filter Rotating Shadowband Radiometer (MFRSR): global and diffuse components of solar irradiance at six narrowband visible and infra-red channels.