A NEW STATISTICAL METHOD OF ESTIMATING SURFACE RADIANCES FROM CORRESPONDING SATELLITE WINDOW-CHANNEL RADIANCES
Abstract Stepwise linear regressions for the specification of blackbody surface radiances are computed using a set of 103 model atmospheres chosen originally by Wark et al. and the corresponding simulated values of Nimbus 2 window-channel (10–11 µ) radiances. Two stratifications are considered: (a) precipitable water vapor, u>1, and (b) u<1 gm cm–2. For each of five zenith angles considered, significant contributions are made in both regression formulas by inclusion of parameters representing the radiative transfer effects of water vapor and ozone. This regression formulation makes use of empirically derived expressions related to these effects over long atmospheric paths. The specification of the sample of surface radiances is in accordance with a multiple correlation coefficient, exceeding 0.990 and 0.995 in the respective stratifications. Corrections for atmospheric effects to be applied to Nimbus 2 window-channel radiances in estimating the corresponding surface values are displayed in nomogramic as w...
Experimental approaches to remote atmospheric probing in the infrared from satellites
Thirteen different types of radiometric instruments either were flown in orbit or are scheduled to fly on forthcoming satellites. A fourteenth type, a very high resolution radiometer for geosynchronous altitude, is among several of the others whose development was stressed for the Global Atmospheric Research Program. Characteristics of each radiometric instrument and some applications of the different types of data are discussed.
Geographic And Environmental Influence On Maya Settlement Patterns Of The Northwest Yucatan: An Explanation For The Sparsely Settled Western Cenote Zone
Most settlement pattern research and GIS analysis of the ancient Maya of the Northern Yucatan have focused on water availability in a dry landscape where cenotes are often the only water source. While water is of paramount importance, permanent settlement secondarily requires farmable soil, a resource often as precious as water in many parts of the Yucatan. The dynamics between these resources reveal areas of ideal settlement and more challenging landscapes for which the Maya developed strategies to overcome environmental conditions. A region of the southwest "Cenote Zone", however, appears to have presented the ancient Maya with insurmountably poor environmental conditions despite abundant water resources. The lack of dense population and stone architecture in this area emphasizes the lack of a simple correlation between cenotes and settlement. This thesis uses GIS analysis to identify and explore such problematic settlement areas to better understand the factors and complexities involved in the more successful settlements of neighboring regions. iv This work is dedicated to my late father, who first introduced me to the Mundo Maya through a visit to the ruins of Tikal at the age of nine, and who instilled in me strength, curiosity, and a love for exploring the world. v ACKLOWLEDGEMENTS I'd like to acknowledge Dr. Arlen Chase and Dr. Diane Chase for providing such outstanding opportunities and instruction, and for leading by example both in the field and in the classroom. Dr. John Walker for his eye-opening perspectives, GIS instruction, inspiring hard-working attitude, and patience in the field. Dr. Clifford Brown and Dr. Walter Witschey for their invaluable correspondence and for their contributions to mapping and GIS data of Maya sites.