Seminars

Lecturer: Dr. Isaac Moradi (U. of Tehran)
Date: 2008-06-03 10:00
Place: IRV, Sal A

Mapping global solar radiation over Iran through Meteosat images

Isaac Moradi, Ph.D. in Climatology
Dept. of Physical Geography
Faculty of Geography,
University of Tehran,
Tehran - Iran

Mapping global solar radiation over Iran through Meteosat images

The overall climate of Iran is semi-arid with clear skies providing enormous amount of solar radiation. The continuous increasing price of oil and its environmental pollutants make the use of clean solar energy very reasonable. Radiometric stations are sparse and the unique method to exploit solar radiation maps is digital image processing of geostationary satellites.
The aim of this study was to evaluate the Heliosat-II method using measured irradiation data the HRVI images of Meteosat-5. The basic idea of the Heliosat method is that the amount of cloud cover over a given area statistically determines the global radiation for the area. The results revealed that the Meteosat data can be used for mapping global solar irradiation over Iran with a ground resolution of ~ 3×3 km. This accuracy is a great opportunity for a country such as Iran to produce an accurate solar radiation atlas.

Comparing UTH exploited from AMSU-B Images with Southern Great Plain radiosonde data

In 1997, the Intergovernmental Panel on Climate Change (IPCC) reported that the mean global temperature will rise about 3 degrees Celsius, tropical climates will mitigate to the north and as a result disease-carrying insects will move northward and cause more damages. Upper Tropospheric Humidity (UTH) plays an important role on the global warming due to its effect on outgoing longwave radiation. Buehler et al (2006) stated that for a tropical scenario a 20% changes in humidity has a more significant impact than the doubling of the CO2 concentration. UTH has vertical, horizontal and temporal variations. Theoretically it is possible to use radiosondes data to create maps of UTH but the only practical method to study temporal and horizontal variations of UTH is using satellite infrared and microwave images. Infrared data are more affected by clouds but microwaves are less sensitive.
The aim of this study was to compare radiosonde humidity data (Measured data by ARM at southern Great Plain station, USA) with Advanced Microwave Sounding Unit (AMSU-B) satellite humidity data. The relative mean biases and relative standard deviations were less than 9% and 6%, respectively.


Created 2008-05-28 11:51:11 by Mats Holmström
Last changed 2008-05-28 23:21:32 by Mats Holmström