Frequently Asked Questions
- What does the acronym EASE in EASE-Grid stand for?
- Why equal-area maps?
- What resolution does the EASE-Grid have?
- What is EASE-Grid 2.0?
What does the acronym EASE in EASE-Grid stand for?
EASE-Grid stands for Equal-Area Scalable Earth Grid and refers to the set of three equal-area projections (North and South azimuthal, and global cylindrical), combined with an infinite number of possible user-defined grid definitions.
Why equal-area maps?
Given the choices of either shape distortion or areal distortion or both, the equal-area projections were chosen for the EASE-Grids because they minimized the amount of distortion over the hemispheric and global scale being portrayed. One convenient side effect of this choice is that calculations of areal statistics are reduced to simply summing pixels and multiplying by a constant area per pixel, so the acronym, EASE takes on a secondary meaning, as in easy to use. For more information, see the EASE-Grid: A Versatile Set of Equal-Area Projections and Grids Web page.
What spatial resolution does the EASE-Grid have?
The EASE-Grid consists of a set of three equal-area projections, combined with an infinite number of possible grid resolutions. An array of gridded data consists of one data element for each grid cell or lattice point. The user has complete flexibility to define the meaning of each grid cell value, according to the most appropriate binning technique for the data and application at hand. Popular EASE-Grid resolutions for data at NSIDC are the 25 km, 12.5 km, 5 km, and 1.25 km grids.
What is EASE-Grid 2.0?
EASE-Grid 2.0 is the newest version of EASE-Grid. It allows for formatting to GeoTIFF without reprojection; prevents avoidable software reprojection issues; provides simpler nested grid definitions, which in turn allow grid definitions at multiple scales to share exact spatial coverage; provides separate cell sizes between cylindrical and azimuthal grids, making it easier to document and use the azimuthal grids; and eliminates undefined grid coordinates at the azimuthal grid corners. For a detailed comparison between EASE-Grid and EASE-Grid 2.0, please refer to the Versions page. For a complete description of EASE-Grid 2.0, refer to the EASE-Grid 2.0 Format Description page.