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本帖主要收录AMSU,AMSR2,GMI,MWRI等微波探测仪器的台风成像图。
什么是微波成像？其原理是用微波照射被测物体，然后通过物体外部散射场的测量值来重构物体的形状或（复）介电常数分布。光学图像只能看到物体的“表面”，比如我们只能在有光线，而且没有遮挡的情况下看见目标物体的影像。微波具有“穿透”能力，因此微波图像反映了物体的温度和介电特性等信息。比如对海洋表面温度的监测，利用微波仪器我们可以获取白天和夜间的洋面温度信息，而且这些信息的获取不受天气的影响，在有云覆盖的情况下，我们一样可以获取洋面温度信息。不同微波频段具有不同的穿透能力。一般来说，频率越低穿透能力越强。通过选择不同频率进行观测成像，我们可以获取不同的目标信息。

AMSU-A uses oxygen absorption bands/lines for atmospheric temperature sounding. Window channels at 23.8, 31.4 and 89 GHz provide information on surface temperature and emissivity.
Thirty consecutive scene resolution cells are sampled in a stepped-scan fashion every eight seconds, each scan covering about 50 degrees on either side of the subsatellite path. These scan patterns and geometric resolution translate to a 48 km diameter cell at nadir and a 2,074 km swath width from the 837 km nominal orbital altitude.

The Microwave Humidity Sounder (MHS) is a self-calibrating, cross-track scanning, five-channel microwave, full-power radiometer, operating in the 89 to 190 GHz region, instrument scans the surface of the Earth three times every eight seconds, taking 90 pixels across the Earth view each scan.
The five channels are co-registered, with each pixel being separated by 1.111 degrees in angle. At nadir, the instrument footprint corresponds to a circle of diameter approximately 16 km. The full swath of the instrument is approximately 1920 km.
MHS channels H1 at 89.0 GHz and H2 (157 GHz) are window channels that detect water vapour in the very lowest layers of the atmosphere and also observe the Earth’s surface.

The Advanced Microwave Scanning Radiometer 2 (AMSR2,) which will be loaded onto the GCOM-W, is a sensor to observe radiometers, or microwaves emitted naturally from the ground, sea surface and atmosphere, using six different frequency bands ranging from 7 GHz to 89 GHz. The antenna of the AMSR2, which receives microwaves from the ground, arc scans the ground surface at a ratio of one turn every 1.5 seconds and observes an area approximately 1,450 kilometers wide in one scan. Using this scanning method, the AMSR2 can observe over 99 percent of the Earth's area in just 2 days.

The Global Precipitation Measurement (GPM) Microwave Imager (GMI) instrument is a multi-channel, conical- scanning, microwave radiometer serving an essential role in the near-global-coverage and frequent-revisit-time requirements of GPM. The instrumentation enables the Core spacecraft to serve as both a precipitation standard and as a radiometric standard for the other GPM constellation members.
The GMI is characterized by thirteen microwave channels ranging in frequency from 10 GHz to 183 GHz. In addition to carrying channels similar to those on the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), the GMI carries four high frequency, millimeter-wave, channels near 166 GHz and 183 GHz.
The GPM Microwave Imager (GMI) has a swath 550 miles (885 kilometers) wide, giving it a broad view of cyclones and other storm systems. The GMI instrument has 13 channels, each displayed in this visualization of the data. Each channel is sensitive to a different frequency of microwave energy naturally emitted from or affected by precipitation.

MWRI is a conical scanning microwave imager at five frequency points with dual polarizations (10 channels). The sensor measures thermal microwave emission of land and ocean surfaces, and measures various forms of water in the atmosphere, clouds, and surfaces. At higher-frequency channels, such as 89 GHz, the scattering signature from the cloud and precipitation are also good indicators for detecting rainfall over land and ocean. The spatial resolutions are from 12 to 80 km, depending on the wavelengths.

可能大部分人没见过MWRI，先放几张样张



啵啵主要制作MWRI的底层，订购格式：具体到天的时间，大致经纬度。时间范围：2010.11.8至今

订购，2013/11/7，10N，127E左右，哪个台风不用说了

订购鹅宝二巅，2020年10月31日，14N，127E左右

纳我来做AMSR2吧
订购格式还是一样（具体到天的时间，经纬度），时间范围是2012-07-03至今。AMSR2的图像在NRL上是有存档的，但是有时有缺档，且NRL的色阶在150~180K无变化，因此我们认为自己渲染AMSR2图像还是有意义的。
关于渲染的图像：
1.若无要求，默认渲染89ah
2.添加了180~100K的色阶（这个色阶180K转紫色，150K过渡到白色，100K过渡到深蓝，是非官方色阶，如果不囍的话我们可以去掉哒）
3.标注的时间不一定完全准确，可能有几分钟的偏差
4.将在标题上附上Weak Link：xxx K，即成环亮温。我们目前无法实现自动测量成环温度，因此是手动读取的
5.会同时渲染两张图像，分别为原分辨率和插值后
示例图：


Carl有时可能咕咕咕，这个寒假有点忙，而且还有隔壁VIIRS的云图要做，请谅解

半边150的狠台，但是由于一个像素成环
此时距离巅峰12h，巅峰没扫中

好家伙，155K（此处再次提醒amsr2的偏强）

就是这张（