Vertical distribution of clouds in Central Amazon from the measurements of a ceilometer

• Grant number: 16/24312-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2017
• Effective date (End): December 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Meteorology
• Principal researcher: Eduardo Landulfo
• Grantee: Amanda Vieira dos Santos
• Home Institution: Instituto de Pesquisas Energéticas e Nucleares (IPEN). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 13/05014-0 - GoAmazon: interactions of the urban plume of Manaus with biogenic forest emissions in Amazonia, AP.PFPMCG.TEM

Abstract

Clouds are important agents of the global climate system for being able to significantly altering Earth's energy balance, affecting the system in time scales ranging from minutes to climate change. Some types of clouds significantly reflect the solar radiation, cooling the planet, while others are semi-transparent but still block the outgoing thermal radiation emitted by the surface and that would otherwise be lost to space, thus warming the planet. Despite its importance, physical processes governing clouds are still not fully known and there is a lack of continuous observations with high enough temporal and spatial resolution to resolve them. Numerical models, for instance, still fail in reproducing the diurnal cycle of cloudiness and precipitation. In this project, the student will study the diurnal cycle of the vertical distribution of clouds in the central Amazon region. Data from the ceilometer operated during the GoAmazon 2014/15 at the experimental site T3-Manacapuru will be used. Clouds will be detected using an automatic algorithm developed in our laboratory for a Lidar, a similar instrument. It can determine the altitude of the cloud base, top, maximum backscatter and the thickness of the cloudy layer. The student will adapt this algorithm for the ceilometer and process all data it has collected during GoAmazon. The student will perform a descriptive statistical analysis with this dataset, and will also calculate the diurnal cycle of the vertical profile of the frequency of occurrence of clouds. Results will be interpreted with help of the thermodynamic profiles and will be compared with results from the literature. (AU)