编辑-地球科学江南体育网页版堆栈交换江南电子竞技平台

你不是登录．您的编辑将被放置在队列中，直到完成同行评议．

我们欢迎编辑，使文章更容易理解和更有价值的读者。因为社区成员会审查编辑，所以请尽量让帖子比你发现它的时候更好，例如，通过修改语法或添加额外的资源和超链接。

牧师

将Sentinel-5P数据中的NO2浓度从mol/m2转换为地面上的μg/m3

Sentinel-5P卫星提供了高分辨率数据产品几种大气微量气体(NO₂,所以₂阿,_3.，以及其他)，以摩尔/ m²在总柱或对流层柱内的是否有可能推断对流层某一特定部分的浓度?

也就是说，我想要得到NO₂栅格在GIS中工作，其中每个像素将包含NO₂水平μg / m^3.，距离地面0-50米。我已经读过了产品用户信息，算法理论基础文档,输入输出数据定义与相应的哨兵-5号有关₂产品。但是，它并没有告诉我如何得到μg/m^3.在地面附近。这可行吗?我想是的，就像哥白尼欧洲空气质量门户，他们使用Sentinel-5P数据进行空气污染预测，我看到他们显示没有₂浓度单位为μg/m3。

是否有一些工作流程?

来自哥白尼欧洲空气质量门户网站的截图:

附注:我在陆地表面遥感和地理信息系统方面有丰富的经验，但我以前从未处理过天气/大气数据。

回答

>……在总柱或对流层柱内以mol/m²测量。是否有可能推断对流层某一特定部分的浓度?不完全是，因为你缺少了一个关键的信息:垂直分布。*结合卫星数据和模型来估算近地表NO₂。根据其他因素，该模型可以估计出哪些表面条件可能与哪些总柱条件相关联。*坚持使用总列数据。*使用不同的数据源，最好是地面测量。尽管四肢测深仪在获得高垂直分辨率方面做得更好(以牺牲水平分辨率为代价)，但在50米以下就太接近地面了。用向下看的传感器测量垂直分布是困难的。 You can get some information with vertical sounding by having many closely-spaced channels along a spectral line, but the vertical resolution is going to be very poor, *in particular* from space. Vertical sounding is common practice for temperature and water vapour, but if you search for NO₂ vertical sounding, you will find mostly, probably exclusively, ground-based measurements. I've tried to do CH₄ sounding and you're lucky if you can get 2 degrees of freedom of signal (DOFS), meaning a rough split in "lower half" or "upper half", but usually you get much less than that: [![information content][1]][1] *Source: [Holl et al., (2016)][Holl]* TANSO-FTS is a spectrometer carried on a satellite, PEARL-FTS is a ground-based instrument looking up. Now this was for CH₄ (not NO₂) and for a station in the Arctic at night. Hopefully you're not trying to do this in the Arctic and not at night, so if you try to retrieve profiles from a spectrometer (AIRS, IASI, CrIS) you can do a better job, but near-surface, probably not. Looking up, such as PEARL-FTS does, tends to be easier than looking down because you don't have a background surface to deal with. There are plenty of [instruments that can retrieve NO₂ total column][NO2]: [![total column from WMO Oscar][2]][2] *Source: [WMO Oscar][NO2]* However, to get a good quality profile from space you need a limb sounder, [such as these][limb]: [![limb sounders, WMO oscar][3]][3] *Source: [WMO Oscar][limb]* A limb sounder gets a much better vertical resolution, but a much worse horizontal and temporal resolution (there are no geostationary limb sounders, and the concept wouldn't make much sense). You can find [a limb viewing geometry illustration here][RGlimb]: [![limb geometry][4]][4] *Source: [Riese et al. (2014)][RGlimb]* The best signal to noise ratio are from solar occultation limb sounders such as [ACE-FTS][ACE], but those can only measure at sunrise and sunset. And close to the surface is difficult with any limb sounder, solar occultation or not, so it is unlikely that a limb sounder would even work in your case of measurements within 50 metre from the surface. Depending on your scientific background, I would either look for model data or use ground-based measurements. ---- * [Holl], G., Walker, K. A., Conway, S., Saitoh, N., Boone, C. D., Strong, K., & Drummond, J. R. (2016). Methane cross-validation between three Fourier transform spectrometers: SCISAT ACE-FTS, GOSAT TANSO-FTS, and ground-based FTS measurements in the Canadian high Arctic. Atmospheric Measurement Techniques, 9(5), 1961-1980. * Riese, M. & Oelhaf, H. & Preusse, P. & Blank, Joerg & Ern, M. & Friedl-Vallon, Felix & Fischer, H. & Guggenmoser, Tobias & Höpfner, Michael & Hoor, Peter & Kaufmann, M. & Orphal, Johannes & Ploeger, Felix & Spang, Reinhold & Suminska-Ebersoldt, O. & Ungermann, Jörn & Vogel, B. & Woiwode, W.. (2014). Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) scientific objectives. Atmospheric Measurement Techniques. 7. 1915-1928. 10.5194/amt-7-1915-2014. [NO2]: https://www.wmo-sat.info/oscar/gapanalyses?variable=106 [limb]: https://www.wmo-sat.info/oscar/gapanalyses?mission=25 [RGlimb]: https://www.researchgate.net/figure/Limb-viewing-geometry-for-a-limb-sounder-The-instrument-measures-the-radiance-emitted-by_fig9_261013184) [ACE]: https://www.wmo-sat.info/oscar/instruments/view/6 [Holl]: https://www.atmos-meas-tech.net/9/1961/2016/ [1]: https://i.stack.imgur.com/1sFuf.png [2]: https://i.stack.imgur.com/3WTRV.png [3]: https://i.stack.imgur.com/drTRB.png [4]: https://i.stack.imgur.com/mpz17.png

编辑总结

取消

\ begingroup美元我认为我会坚持将Sentinel-5P数据与一些模型结合起来，以估算近地表NO₂。谢谢你详细的回答。 \ endgroup美元
- - - - - -雅罗斯拉夫牛
2020年3月6日18:31

添加评论 |

纠正小的拼写错误
阐明意思而不改变它
添加相关资源或链接
总是尊重作者的意图
不要用编辑回复作者

使用反撇号'或波浪号~创建代码围栏
' ' '
像这样
' ' '
添加语言标识符以突出显示代码
”“python
def函数(foo):
打印(foo)
' ' '
在段落之间放置返回
对于换行符，末尾加2个空格
_italic_或* *的* *
通过将>放在行开始来引用
要建立链接(尽可能使用HTTPS)
< https://example.com >
(例子)(https://example.com)
< a href = " https://example.com " > < / >示例
MathJax方程罪\ \ ^ 2θ美元

格式帮助:
回答帮助:

MathJax help»