Aqua/AMSR-E L3 AMSR2 Format Sea Surface Temperature (1-Month, 0.25 deg)

Aqua/AMSR-E L3 AMSR2 Format Sea Surface Temperature (1-Month, 0.25 deg) dataset is obtained from the AMSR-E sensor onboard Aqua and produced by the Japan Aerospace Exploration Agency (JAXA). Aqua of NASA was launched on May 4th, 2002 in Sun-synchronous sub-recurrent Orbit. Aqua observes various kinds of physical phenomena related to water and energy circulation from space. Aqua data promoted the research activities for interactions between the atmosphere, oceans and lands, and their effects on climate changes. AMSR-E scans the Earth's surface by mechanically rotating the antenna and acquires radiance data of the Earth's surface. Each frequency band is monitored by vertical and horizontal polarized wave. It conically scans and keeps an angle of incidence on the earth surface (a nominal of 55 degrees) and accomplishes a swath width of about 1450 km. The AMSR-E reached its limit to maintain the antenna rotation speed necessary for regular observations, and the AMSR-E restarted its observation in slow rotation mode (2 rotations per minute) on December 4, 2012. However, the AMSR-E reached its limit to maintain the antenna rotation speed necessary for slow rotation mode and it automatically halted its observation and rotation on December 4, 2015. Level 3 data inputs level 1B and level 2 data and projected to the map in accordance with the specified projection technique (Equi-Rectangular (EQR) or Polar Stereographic (PS)), and then averaged temporally and spatially. These statistical values are computed for observation data on ascending orbit and descending orbit respectively. This product includes monthly mean Sea Surface Temperature (SST) and Static information. The relationship between 6V (or 10V) and SST is calculated by using the complex relative dielectric constant. The physical quantity unit is degree. The following Static information is included: Standard_Deviation: standard deviation value for each pixel. This item is only stored in monthly product. Average_Number: the number of valid physical quantity data (except error and missing) which was used to determine "Geophysical Data". Total_Number: the number of physical quantity data included in the grid (include valid and invalid). The provided format is HDF5. The spatial resolution is 0.25 deg. The statistical period is 1 month. The current version of the product is "Version 8". The projection method is EQR. The generation unit is global.

Aqua/AMSR-E L3级AMSR2格式海表面温度（1个月统计周期，0.25度空间分辨率）数据集由搭载于美国国家航空航天局（National Aeronautics and Space Administration, NASA）Aqua卫星的AMSR-E传感器获取，并由日本宇宙航空研究开发机构（Japan Aerospace Exploration Agency, JAXA）制作。Aqua卫星于2002年5月4日发射，运行于太阳同步亚回归轨道。该卫星从太空观测与水循环、能量循环相关的各类物理现象，其数据推动了大气、海洋与陆地间相互作用及其对气候变化影响相关的研究工作。

AMSR-E通过机械旋转天线扫描地球表面，获取地球表面的辐射亮度数据，各频段分别通过垂直极化波与水平极化波进行监测。该传感器采用圆锥扫描方式，对地入射角固定为标称值55度，扫描幅宽约1450千米。AMSR-E后续难以维持常规观测所需的天线转速，于2012年12月4日切换至低速旋转模式（每分钟2圈）恢复观测；但随后仍无法维持该模式下的天线转速，最终于2015年12月4日自动停止观测与天线旋转。

L3级数据以L1B与L2级数据为输入，按照指定的投影技术（等经纬度投影（Equi-Rectangular, EQR）或极地方位投影（Polar Stereographic, PS））进行地图投影，随后开展时间与空间平均处理。上述统计值分别针对升轨与降轨的观测数据计算得到。本产品包含月均海表面温度（Sea Surface Temperature, SST）与静态信息。6V（或10V）与SST之间的关系通过复相对介电常数计算得到，该物理量的单位为摄氏度。

本产品包含以下静态信息：
1. 标准差（Standard_Deviation）：各像元对应的标准差数值，该字段仅在月尺度产品中存储；
2. 有效数据量（Average_Number）：用于计算"Geophysical Data"的有效物理量数据总数（排除错误与缺失数据）；
3. 总数据量（Total_Number）：网格内包含的全部物理量数据总数（涵盖有效与无效数据）。

本数据集采用HDF5格式存储，空间分辨率为0.25度，统计周期为1个月，当前版本为Version 8，投影方式为等经纬度投影（EQR），生产范围为全球尺度。