The Prediction and Research Array in the Tropical Atlantic (PIRATA) consists of 18 moorings spanning the tropical Atlantic Ocean. Several of the moorings are directly downwind from the Sahara and Sahel regions of Africa, which together represent the largest source of mineral dust on the planet.Dust and biomass burning aerosols accumulate on the moorings' solar radiometer domes, leading to biases as large as -150 W m -2 (the average surface solar radiation is about 250 W m -2 at these locations). These biases make it difficult to quantify the role of changes in cloudiness and aerosols on surface solar radiation, which is an important driver of sea surface temperature. Scientists and engineers at AOML are developing an automated radiometer dome cleaner that will rinse aerosols from the dome at regular 24-hour intervals while the instrument is deployed at sea. A prototype was deployed on the PIRATA mooring at 11.5°N, 23°W in January 2015 and will be recovered in December 2015. The goal is to develop a radiometer dome cleaner that is thorough and reliable enough to be installed regularly on the PIRATA moorings.
The radiometer and its cleaner mounted to a PIRATA buoy and ready for deployment in January 2015. The radiometer is the instrument in the upper right corner of the picture, with small circular glass dome surrounded by larger white circular shield. The cleaner consists of three white nozzles that periodically draw water from a container on the lower tower platform and squirt it at the radiometer's glass dome.