Research

My research focuses on the bidirectional interaction between the biosphere and the free atmosphere through the exchange of energy, water, carbon and other trace gases mediated by the atmospheric boundary layer. One of the major theme has been to understand how energy, water and carbon cycle respond to changes in climate, landcover and disturbances (drought, harvest, fire). These studies utilized eddy-covariance observations of surface fluxes over many ecosystems, including grasslands, arid lands, croplands, wetlands, temperate and Boreal forests . Many of these sites are part of FLUXNET, AmeriFlux and FLUXNET Canada networks.

I am also interested in improving atmospheric measurement techniques and sensors, to perform innovative field experiments using sensors different platforms (in situ, aircraft, sUAVs and satellite) and remote sensing to improve our understanding of atmospheric processes at various levels. For my research I have participated in field campaigns and analyzed data from tower/ship-based micrometeorological sensors and eddy covariance systems, ABL soundings (Rawinsonde, Tethersonde, GPS Sonde), ground-based remote sensing instruments (SODAR, L-band UHF radar and Indian Mesospheric Stratospheric Tropospheric (MST) – VHF Radar), and airborne (aircraft and unmanned aerial vehicle (UAV)) meteorological instruments, imagers (hyperspectral, thermal and LiDAR) and flux sensors (BAT probe).

Current projects

Bridging the scale gap between local and regional methane and carbon dioxide isotopic fluxes in the Arctic (funding NSF)

This project aims to bridge the scale gap between local studies of carbon emissions in the Arctic, such as those from flux towers, and large regional scale emissions estimates from inversion modeling. This involves emission measurements of CO2 and CH4 plus nitrous oxide (N2O), and water vapor (H2O) from the North Slope of Alaska on a small aircraft operating at altitudes from 10 m to 10 km, with custom-built spectroscopic sensors, an air turbulence probe, and GPS systems. [Collaborators: Harvard University]

Modeling the impact of climate and land cover changes on the social organization of Octodon degus (funding ODRD)

The aim of this project is to develop a predictive framework for how harsh environmental conditions (low or variable rainfall, high temperature, drought) and changes in land cover impact mammalian social organization (SO). [Collaborators: University of Tennessee Chattanooga ]

Selected Research Topics

• • Land surface temperature using ground, aircraft and satellite -based measurements

  • Energy exchange and evapotranspiration over two semi-desert grasslands in Arizona

  • Carbon balance in Pacific Douglas-Fir stands following harvesting

  • Effect of drought on Carbon Balance of boreal forests

  • Ventilation coefficient over a tropical Indian station, Gadanki (13.5°N, 79.2°E)

  • Intraseasonal oscillations in the tropical lower atmosphere during monsoon and winter seasons