IIA Institutional Repository

Validation of water vapor retrieval from Moderate Resolution Imaging Spectro-radiometer (MODIS) in near infrared channels using GPS data over IAO-Hanle, in the trans-Himalayan region

Show simple item record

dc.contributor.author Shantikumar, N. S
dc.contributor.author Jade, S
dc.contributor.author Shrungeshwara, T. S
dc.contributor.author Song, H.-J
dc.date.accessioned 2020-11-17T12:01:40Z
dc.date.available 2020-11-17T12:01:40Z
dc.date.issued 2016-01
dc.identifier.citation Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 137, pp. 76-85 en_US
dc.identifier.issn 1364-6826
dc.identifier.uri http://prints.iiap.res.in/handle/2248/7073
dc.description Restricted Access © Elsevier http://dx.doi.org/10.1016/j.jastp.2015.11.019 en_US
dc.description.abstract Integrated precipitable water vapor (PWV) retrieved from Moderate Resolution Imaging Spectro-radiometer (MODIS) in near-infrared channels is examined with the PWV estimated from the Global Positioning System (GPS) data and measured surface temperature and pressure values over Hanle, located at a high-altitude (∼4500 m) trans-Himalayan region. Since the accuracy of MODIS derived PWV over the large elevated topography of the region is not well studied, the present work focus on the validation of MODIS PWV using the GPS data during 2005–2012. The study reveals that MODIS PWV compares well with the GPS PWV data with bias 0.018 cm, root mean square error (RMSE) 0.137 cm and coefficient of determination (R2) 0.91. The two types of data products are compared on short (daily) and long temporal (monthly-seasonal) scales in order to evaluate the seasonal dependence of PWV. The peak values of PWV from MODIS and GPS data at the site varied from 1.7 to 2.05 cm and 1.2 to 1.4 cm as the daily and the monthly means, respectively, which occurred during August. However, the seasonal peak of PWV occurred during summer as 0.88 and 0.97 cm for MODIS and GPS data, respectively. The present study noticed that about 85% of the total PWV estimated from MODIS as well as GPS data lies below 1.0 cm over the site. The seasonal study of PWV reveals that MODIS data is found to be underestimating the PWV when compared to GPS data with bias 0.095 cm and RMSE 0.215 cm particularly during summer. This is due to dry and high-altitude terrain of Hanle particularly during summer months. However, there are marginal differences (bias varied from 0.007 to 0.017 cm) during the remaining seasons and seasonally R2 varies from 0.62 to 0.87. GPS PWV exhibits distinct diurnal cycle with minimum in morning as well as in night and peak in the late afternoon (16–18 h) irrespective of the seasons. However, the diurnal cycle is very prominent during summer than the rest of the seasons. en_US
dc.language.iso en en_US
dc.publisher Elsevier B.V en_US
dc.subject GPS en_US
dc.subject Near-infrared channels en_US
dc.subject Precipitable water vapor en_US
dc.subject High-altitude terrain en_US
dc.title Validation of water vapor retrieval from Moderate Resolution Imaging Spectro-radiometer (MODIS) in near infrared channels using GPS data over IAO-Hanle, in the trans-Himalayan region en_US
dc.type Article en_US


Files in this item

This item appears in the following Collection(s)

Show simple item record

Search DSpace


Browse

My Account