The Dynamic Earth is slowly moving with increasing trend of population, the movement of the Earth with the population making the Earth’s Environment more dynamic. Population dynamics - rural versus urban, and its impact on the Earth’s Environment and Natural Resources will be presented. Climate change and its relation with the growing population will be discussed in the declining of the hydrological resources especially of the Indo-Gangetic plains in the northern part of India.

The Geography Seminar Series is organized by the Geographical Honors Society Gamma Theta Upsilon Eta Omicron Chapter.

Electron temperature (Te) in the topside ionosphere and plasmasphere
is an important parameter because thermal electrons play a key role in
the energy balance of these regions. The IRI (International Reference
ionosphere) model includes an empirical representation of Te in the
topside ionosphere depending on altitude, latitude, local time, and
season. But due to a lack of data and sometimes conflicting
measurements, the solar activity variation of Te has not been reliably
modeled so far.

We have made good progress in modeling the Te behavior with the help
of a large database of satellite electron temperature measurements,
and of Incoherent Scatter Radars observations, and with the assistance
of simulations with the theoretical FLIP model. The presentation will
focus in particular on (1) comparison of calculation of the FLIP model
with data (2) latitudinal and altitudinal variation of Te and the heat
flux (3) discussion prevailing cooling and heating terms influencing
Te balance and causing its changing with solar activity. We will also
discuss development of a new global Te model with the Te solar
activity variation as a correction term which can help to improve
current Te model in IRI.

Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument for NASA’s Earth Observing System (EOS), currently operated on-board the Terra spacecraft launched in December 1999 and Aqua spacecraft launched in May 2002. MODIS was developed with improvements over its heritage sensors in terms of its spectral, spatial, and temporal coverage. It makes observations in 36 spectral bands with wavelengths from visible (VIS) to long-wave infrared (LWIR) and at three spatial resolutions (250m, 500m, and 1000m at nadir) with a complete global coverage in less than two days. Since launch, more than 40 science data products have been continuously generated and extensively used by scientists worldwide for their studies of the Earth system of land, oceans, and atmosphere. In order to maintain its on-orbit calibration and science data product quality, MODIS was built and operated with a comprehensive set of on-board calibrators (OBCs), which include a solar diffuser (SD), a solar diffuser stability monitor (SDSM), a blackbody (BB), a deep space view (SV) port, and a spectro-radiometric calibration assembly (SRCA). This talk provides an overview of MODIS on-orbit calibration methodologies, activities, and efforts made by the MODIS Characterization Support Team at NASA/GSFC. It illustrates examples of Terra and Aqua MODIS radiometric, spatial, and spectral performance derived from their multi-year on-orbit observations. Discussions will focus on, but not limited to, the use of sensor OBCs. Other approaches and activities developed to support MODIS on-orbit calibration and characterization, such as using regularly scheduled lunar observations and carefully selected ground targets, will also be presented.