Description
Summary:Clouds and their radiative effects have very large uncertainties in present climate models and their quantification continues to be a challenge. 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. From this, aerosol optical depth may be inferred. 4) Parsivel disdrometer: raindrop size distribution 5) Cimel sun photometer: measures direct solar irradiance and sky radiance Data frequency is around 1-minute resolution. Data collected continuously except for unexpected instrument down times (which have happened). Data available from the ARM archive. Search 'MCQ' at http://www.archive.arm.gov/discovery Quality-controlled data from the various cloud, radiation and precipitation remote-sensing instruments installed by ARM at the Clean Air Laboratory as part of AAS 4292.