|Title||Monitoring surface properties in the Arctic: Unique value of HEO (Molniya) system to complement polar LEO observations for climate|
|Author||Trishchenko, A P|
|Source||Arctic imaging workshop, presentations; 2008, 34 pages|
|Links||Online - En ligne|
|Alt Series||Earth Sciences Sector, Contribution Series 20080282|
|Meeting||Arctic imaging workshop; Copenhagen; DK; August 21, 2008|
|Subjects||geophysics; Nature and Environment; remote sensing; satellites; satellite imagery|
|Illustrations||graphs; plots; images; satellite images|
|Program||Enhancing resilience in a changing climate |
To better understand and quantify the processes of climate change in the Artic requires complex observations that rely substantially on satellite data. Monitoring the surface
properties in the Arctic is one of the high priority directions at the Canada Centre for Remote Sensing (CCRS) (http://www.nrcan-rncan.gc.ca/com/elements/issues/23/arcti-eng.php). This work is based on principles laid out by the GCOS (GCOS-107,
WMT/TD 1338) and CEOS Implementation Plan. So far, this work was mainly based on observations from polar orbiting satellites. The most useful data come from the moderate resolution sensors, such as AVHRR, MERIS and MODIS due to wide coverage and
frequent repeat cycle. The overview of technology and results obtained at CCRS on developing long-term satellite data records over Canada and Arctic circumpolar area will be presented. Analysis of two decades of AVHRR 1-km data and MODIS 250-m data
since 2000 indicates some trends in vegetation index, albedo and snow/ice cover.
Several parameters, such as surface radiation budget, snow and ice cover dynamics, surface bi-directional reflectance distribution function (BRDF), aerosol
retrievals and atmospheric correction, require observations at higher temporal resolution and/or variable viewing geometry that cannot be achieved from the Low Earth Orbiting (LEO) polar satellite systems. The Highly Elliptical Orbiting (HEO) system
based on 12-hour Molniya orbit represents a unique opportunity to address this issue. Nearly continuous temporal coverage of Arctic Circle can be achieved from two properly synchronized Molniya-type orbits. An analysis of space time-viewing geometry
sampling and stereo-imaging capabilities for characterization of surface properties, BRDF and surface radiation budgets will be presented. Examples of synthetic images will be shown to demonstrate and better understand the image acquisition issues
associated with variable altitude and spacecraft rotation inherent to highly elliptical Molniya-type orbit. This type of observations is currently planned as part of the Polar Communications and Weather (PCW) mission initiated by the Canadian Space
Agency (CSA) with support from several other government departments.
This study is conducted at the Canada Centre for Remote Sensing (CCRS), Earth Sciences Sector of the Department of Natural Resources Canada as part of the Project J35 of the
Program on "Enhancing Resilience in a Changing Climate".