Index Catalog // ScholarsArchive@OSU

Creator:: Hilker, Thomas, Lyapustin, Alexei I., Hall, Forrest G., Myneni, Ranga, Knyazikhin, Yuri, Wang, Yujie, Tucker, Compton J., and Sellers, Piers J.
Abstract:: The Amazon rainforest is a critical hotspot for bio-diversity, and plays an essential role in global carbon, water and energy fluxes and the earth's climate. Our ability to project the role of vegetation carbon feedbacks on future climate critically depends upon our understanding of this tropical ecosystem, its tolerance to...
Resource Type:: Article

Creator:: Hilker, Thomas, Lyapustin, Alexei I., Tucker, Compton J., Hall, Forrest G., Myneni, Ranga B., Wang, Yujie, Bi, Jian, Mendes de Moura, Yhasmin, and Sellers, Piers J.
Abstract:: We show that the vegetation canopy of the Amazon rainforest is highly sensitive to changes in precipitation patterns and that reduction in rainfall since 2000 has diminished vegetation greenness across large parts of Amazonia. Large-scale directional declines in vegetation greenness may indicate decreases in carbon uptake and substantial changes in...
Resource Type:: Article

Creator:: Hilker, Thomas, Hall, Forrest G., Coops, Nicholas C., Black, Andrew T., Jassal, Rachhpal, Mathys, Amanda, and Grant, Nicholas
Abstract:: Vegetation carbon uptake and respiration constitute the largest carbon cycle of the planet with an annual turnover in the order of 120 GT. Currently, neither ecosystem carbon uptake (through photosynthesis) nor ecosystem carbon release (through respiration) can be measured directly during the daytime. Instead, flux-tower measurements rely on nighttime respiration...
Resource Type:: Article

Creator:: Hilker, Thomas, Hall, Forrest G., Coops, Nicholas C., Collatz, James G., Black, T. Andrew, Tucker, Compton J., Sellers, Piers J., and Grant, Nicholas
Abstract:: Surface energy balance is a major determinant of land surface temperature and the Earth's climate. To date, there is no approach that can produce effective, physically consistent, global and multi-decadal energy–water flux data over land. Net radiation (R[subscript n]) can be quantified regionally using satellite retrievals of surface reflectance and...
Resource Type:: Article

Creator:: Lyapustin, Alexei I., Wang, Yujie, Laszlo, Istvan, Hilker, Thomas, Hall, Forrest G., Sellers, Piers J., Tucker, Compton J., and Korkin, Sergey V.
Abstract:: This paper describes the atmospheric correction (AC) component of the Multi-Angle Implementation of Atmospheric Correction algorithm (MAIAC) which introduces a new way to compute parameters of the Ross-Thick Li-Sparse (RTLS) Bi-directional reflectance distribution function (BRDF), spectral surface albedo and bidirectional reflectance factors (BRF) from satellite measurements obtained by the Moderate...
Resource Type:: Article

Creator:: Hilker, Thomas, Lyapustin, Alexei I., Tucker, Compton J., Sellers, Piers J., Hall, Forrest G., and Wang, Yujie
Abstract:: Tropical rainforests are significant contributors to the global cycles of energy, water and carbon. As a result, monitoring of the vegetation status over regions such as Amazônia has been a long standing interest of Earth scientists trying to determine the effect of climate change and anthropogenic disturbance on the tropical...
Resource Type:: Article

ScholarsArchive@OSU