数据说明
Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data
上传时间:2019-05-23 08:58:06 浏览次数:作者与来源:admin
Sea ice concentration represents an areal coverage of sea ice. For a given grid cell, the parameter provides an estimate of the fractional amount of sea ice covering that cell, with the remainder of the area consisting of open ocean. Land areas are coded with a land mask value. The data are provided in the polar stereographic projection at a grid cell size of 25 x 25 km.

Resolution: 25km pixel, daily, monthly

Duration: 26 October 1978 to 31 December 2017

Source: National Snow and Ice Data Center (NSIDC)

Version: 1

Processing:

This product is designed to provide a consistent time series of sea ice concentrations (the fraction, or percentage, of ocean area covered by sea ice) spanning the coverage of several passive microwave instruments. To aid in this goal, sea ice algorithm coefficients are changed to reduce differences in sea ice extent and area as estimated using the SMMR and SSM/I sensors. The data are generated using the NASA Team algorithm developed by the Oceans and Ice Branch, Laboratory for Hydrospheric Processes at NASA Goddard Space Flight Center (GSFC).

These data include gridded daily (every other day for SMMR data) and monthly averaged sea ice concentrations for both the north and south polar regions. The data are produced at GSFC about once per year, with roughly a one-year latency, and include data since 26 October 1978. Data are produced from SMMR brightness temperature data processed at NASA GSFC and from SSM/I and SSMIS brightness temperature data processed at the National Snow and Ice Data Center (NSIDC).

Known issues

The sea ice concentration data is the gray value, range from 0 to 255. Description of Data values as follows

Description of Data Values

Data Value

Description

0 - 250

Sea ice concentration (fractional coverage scaled by 250)

251

Circular mask used in the Arctic to cover the irregularly-shaped data gap around the pole (caused by the orbit inclination and instrument swath)

252

Unused

253

Coastlines

254

Superimposed land mask

255

Missing data

 

This data set is generated from brightness temperature data derived from the following sensors: the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR), the Defense Meteorological Satellite Program (DMSP) -F8, -F11 and -F13 Special Sensor Microwave/Imagers (SSM/Is), and the DMSP-F17 Special Sensor Microwave Imager/Sounder (SSMIS).

 

Reference

Swift C T, Fedor L S, Ramseier R O. An Algorithm to Measure Sea Ice Concentration with Microwave Radiometers. Journal of Geophysical Research, 1985, 90(C1): 1087-1099. DOI: 10.1029/JC090iC01p01087

Cavalieri D J, Gloersen P, Campbell W J. Determination of Sea Ice Parameters with the Nimbus 7 SMMR. Journal of Geophysical Research, 1984, 89(D4): 5355-5369. DOI: 10.1029/JD089iD04p05355

 

All the contents of this page are quoted from European Centre for National Snow and Ice Data Center. All project documentation and related publications can be found at the website:

https://nsidc.org/data/NSIDC-0051/versions/1