Scientists have gained new insights into the processes that have driven ocean level variations for over a century, helping us prepare for the rising seas of the future. Continuous monitoring of glaciers and ice caps has provided unprecedented insights to global ice loss that could have serious socioeconomic impacts on some regions. Enter the product short name e. A list of available products matching your query will be generated. Select the layer s of interest to add to the Selected layers list.
Layers from multiple products can be added to a single request. If NetCDF4 is selected, outputs will be grouped into files in. Once your request is completed, from the Explore Requests page, click the View icon in order to view and interact with your results.
This will take you to the View Area Sample page. The Layer Stats plot provides time series boxplots for all of the sample data for a given feature, data layer, and observation. If your feature contains attribute table information, you can view the feature attribute table data by clicking on the Information icon to the right of the Feature dropdown. An example of doing this in QGIS is below. There are many options for analysis. Can be used for comparison studies and error analysis.
Solid Earth adjustments from the glacial loading of the last ice age produce long term trends in the Earth's gravity field that need to be accounted for to infer contemporary surface mass changes. The spherical harmonic coefficients of degree 1 represent the distance between the center of mass of the Earth and its 'center of figure', which in practice is the center of a set of tracking stations on the surface of the Earth.
Follow link above for details and download links. Current version: RL06M. These discoveries provide a unique view of Earth's climate and have far-reaching benefits to society and the world's population. The remarkable achievement of the GRACE mission is the culmination of many decades of algorithm development, technological advances, and expansion of computational capabilities.
In John O'Keefe, at NASA GSFC, first proposed the use of artificial satellite tracking data analysis for measuring the Earth's gravity field, and in first observed the J3 term describing the Earth's pear shaped static gravity field with Vanguard 1 tracking data. Since it's beginning in and global expansion in the 's, satellite laser ranging SLR has provided valuable tracking observations that proved capable of resolving much more of the static gravity field than was previously possible, and still produces important measurements of the time-variable J2 term; a measure of Earth's oblateness.
The basic GRACE mission concept to observe Earth's time-variable gravity field with inter-satellite ranging measurements between two low Earth co-orbiting satellites was first proposed by Wolff [] and important algorithms for its implementation were developed by Colombo []. Over the decades, the standard method of gravity determination has been the estimation of spherical harmonics, which are a set of scale factors applied to global periodic functions of different spatial frequencies on the surface of a sphere.
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