An Analysis of Clouds and Radiation from the First Year of Measurements from GOAmazon

Description

Located downwind of the city of Manus, Brazil within the Amazon Rainforest, Manacapuru, Brazil is home to numerous influences on the radiation budget, whether urban or biogenic aerosols, deep convective clouds, or a changing carbon budget due to deforestation. To gain a better understanding of the links between aerosols, clouds, and radiation, the ARM Mobile Facility (AMF) was placed in Manacapuru, Brazil as part of the GOAmazon campaign. Observations of the surface meteorology and radiative fluxes, as well as aerosol and cloud properties will be measured from January 2014 through December 2015 and observations from the first year of the deployment are presented. Although the climate in this area is characterized by a wet and dry season, the average surface relative humidity only differs by about 10% at the heights of the two seasons. The highest values of cloud fraction occur in the early afternoon in the wet season, stretching across the troposphere, while the dry season clouds tend to occur near the surface at that time and centered around 10 km a couple hours later. A large loading of water vapor results in high values of surface downwelling longwave (LW) radiation compared to the upwelling component year round while high values of cloud fraction result in a decrease in the surface downwelling (SW) radiative flux. Using the Clouds and the Earth's Radiant Energy System (CERES) SYN1deg product’s top of the atmosphere radiative fluxes along with the AMF measurements, the radiative flux divergence was calculated on a diurnal time scale. These measurements were then compared to observations of cloud properties to determine how varying cloud types impact the radiation budget in this region.