FAQs

我正在下载数据。什么可能是错的?

We require account registration for access to our data over ftp. You can create an account by visitingregister.remss.com.

如果您已成功下载数据但读取它无法遇到问题,则可能需要更改FTP设置。当二进制数据文件下载为文本(ASCII模式)时,会发生最常见的问题之一,更改和损坏数据。许多FTP客户端将默认情况下执行此操作。在命令行FTP中,在连接和下载之前键入“二进制”。在FTP客户端中,检查设置:文件扩展通常用于确定二进制v。ascii模式。

如果您以二进制模式下载数据,似乎仍然损坏,检查文件大小。FTP服务器报告的字节数应与本地文件系统报告的大小完全匹配。如果不同,请尝试再次下载。

为什么不是我的ftp用户名和密码提供access correctly?

您的默认用户名和密码是您的完整电子邮件地址。如果您尝试通过FTP通过FOR的URL访问数据[ftp://user:password@ftp.remss.com] with the "@" symbol included in your email, it is often unrecognized. For example:

[ftp://xxx@yyy.com:xxx@yyy.com@ftp.remss.com.] will not work correctly. This can be remedied by encoding the "@" symbols in your email address to "%40". The example then becomes: [ftp://xxx%40yyy.com:xxx%40yyy.com@ftp.remss.com]

更新数据时如何了解如何?

我们处理数据的许多仪器都不断更新。其他数据集每月更新一次(即风和蒸气产品通常在每个月的10或11日更新,CCMP每年1月和7月最新两次)。

我注意到一些数据丢失了。我应该怎么办?

如果您注意到一些丢失或空的数据文件,请首先检查它们是否未列为有关特定仪器/测量的网页上缺失。如果不是,请通过支持框联系我们。

Why are some files named .rt and others .v7?

Files in .rt format are “real time” which means that at least some portion of the input data are tentative. Remote Sensing Systems aims to make data available as soon as possible for operational use, but some improvements can be made post-hoc once full atmospheric analyses are available which include in situ measurements. When final processing is complete, the .rt files are removed from the server and replaced with .v7 files. The .rt files are not intended to be research quality. Some possible issues within them include erroneous brightness temperatures and geolocation errors.

我们可以在网站上或文档中使用您的数据吗?

由于我们的数据是公开,因此您可以自由地在文档中和您的网站上使用研究数据。乐动帐号注册我们确实要求你妥善引用我们。有关更多信息,请参阅数据引用页面。我们的资金取决于我们表明其他人使用的数据的能力。通过陈述您在文档中使用RSS数据并提供足够的信用,您可以帮助确保这些重要的数据产品继续自由可用。

Are winds one minute or ten minute mean winds (or equivalents thereof)?

卫星图像是25 km x 25公里区域的瞬时快照。这可能与8-10分钟的风相比(如果您考虑过的风暴测量的空间量,则通过传动于8分钟的定点移动的定点。

我们验证卫星与浮标风风,most of which are temporal averages ranging from 6 minutes (TAO) to 8 minutes (NDBC), and generally obtain wind speed differences of less than 1 m/s.

I need a 5-day averaged product. Can I get that from you?

No. We do provide data from a few instruments at 3, 7, or 8 day averaging intervals due to instrument sampling patterns, but will typically not fulfill specific requests for averaged products. However since we offer all of our products in daily files, you can create your own 5-day running average using the data analysis software of your choice (IDL, Matlab, r, etc…)

How are the 3-day, weekly and monthly average data maps made?

The radiometer (SSM/I, TMI, and AMSR-E) and scatterometer (QuikScat, SeaWinds) data are all available as 3-day, weekly and monthly averaged data. These files are created from the earth gridded daily pass data. Each grid cell contains the average (mean) value of all valid geophysical data points in that cell for all daily passes within the averaging time period. For grid locations where no data exist within the averaging period (occasionally occurs in 3-day maps), a value of 254 (missing data) is assigned.

如果ICE在平均期内的有效数据通常更频繁地存在冰,则冰(值为252)被分配给网格单元。

Do you have any data over land?

不,RSS用于计算风,云水,大气水蒸气含量和雨率仅用于在海洋上使用的算法。CCMP风是在RSS中产生的唯一数据集,具有在土地上的数据,因为它使用时代临时模型风场作为卫星和原位风测量调节的基础。乐动体育官方2.0乐动苹果手机但是,土地数据仍然不受RSS卫星输入的影响,因此数据只是ERA临时背景。

What is the resolution of the data?

可在RSS(GMI,TMI,SSMI / SSMIS,AMSR2,SMAP,WINDSAT)上提供的单卫星数据产品全部提供0.25乘0.25度网格。交叉校准的多平台(CCMP)网格表面向量风也在四分之一栅格上。其他多卫星产品(风和蒸汽)处于1度分辨率。

Why are there limitations on F15 data use? What is wrong with it?

Data from the F15 satellite experienced biases stemming from interference between the radiometer and a radar calibration beacon that was activated in August 2006. Although corrections to the data were made, data quality continued to degrade, especially in 2008 and early 2009. Interference is affected seasonally, and worsens during late winter and early fall when F15 enters the earth’s shadow. More detailed information can be found in the following blog post from 2009这里.

Why do you have negative cloud values in your data? How is this possible? Is this an error?

We use a small negative offset to account for random noise in the data. In clear sky conditions, all cloud values should be zero. However, there is some noise inherent in the data. So in practice, clear sky values average zero. Some are a little above and some are a little below zero. We keep the clear sky values that land a little below zero so that they average out with the clear sky values that land a little above zero. If we set negative cloud retrievals to zero, then it would tend to push the average a little too high.

What is the difference between an 11 GHz wind(lo) and a 37 GHz(med) wind?

We produce two standard rain-free radiometer wind products: WSPD_LF (low-frequency) and WSPD_MF (medium frequency). The first, WSPD_LF is created using the frequency channels at 10.65 GHz and above (see tables above) and is most similar to the only wind offered in the version-5 AMSR-E data files or the first wind of the TMI files. The second, WSPD_MF, uses frequency channels at 18.7 GHz and above and is most similar to the SSM/I and SSMIS winds.

Each wind product has distinct advantages. The WSPD_LF is less affected by the atmosphere and rain, but is affected by 10.65 GHz RFI and sun glitter effects. The WSPD_MF has a higher effective spatial resolution, is less affected by ice and land contamination, and is only slightly affected by sun glitter effects and RFI. The WSPD_MF are a little noisier than the WSPD_LF.

Why do I see data on daily maps with tomorrow's date, when tomorrow has not yet occurred?

Each daily map is for ascending or descending passes of a satellite on that date at Universal Coordinated Time (UTC), also known as Greenwich Mean Time (GMT) and Zulu (Z) time. UTC is the mean solar time at the prime meridian, and is the primary standard time used to regulate clocks around the world. UTC does not observe daylight savings time.

For example, data may be collected in the New York area at approximately 8:30 pm local time. But 8:30 pm in New York City is 1:30 am in Greenwich, England (8:30 + 5 hour time difference). If it is August 17th, local time in New York, it must be August 18th in Greenwich, England, a location with GMT (the date of the map). Thus, some data collected on Aug 17th, local time, will appear on the August 18th map.

Similar time "issues" occur for each of the satellites. The table below demonstrates another example, this time for data collected by the F13 satellite. F13 crosses the equator at approximately 5:30 am.

地点

拉特/ LON

F13当地时间/日期

F1M GMT时间/日期

地图日期

新几内亚 0 / 133 5:30 AM 20-Sep 晚上8:30 19-sep 19世纪9月19日
Jarvis Island 0 / 203 5:30 AM 19-Sep 下午4:30 19-SEP 19世纪9月19日
Ecuador 0 / 280 5:30 AM 19-Sep 10:30 AM 19-Sep

19世纪9月19日

Here, the F13 morning pass time of 5:30 (local time) is used to determine the GMT of the map date. The corresponding GMT time and date are then used to determine the date at the given location. When the September 19th F13 morning pass was collected, it was actually September 20th in New Guinea, a location that is 8 hours ahead of Greenwich.

The best way to determine the time of observations for scientific comparisons is to use the time data in the daily binary data files. Each pixel location of an ocean parameter map has a specific GMT minute of day listed in the time array. Use of time in this manner will keep your data processing and intercomparisons in the correct order.

How can I tell when a satellite collected data over a particular spot on a daily data map?

The time parameter can be extracted from each daily binary data file using read routines available on our FTP site (see the Data Description for each instrument). A visual method for quick approximations is discussed in:Support / Crossing Times / Swath Time Labels.

Who names tropical cyclones and how do they generate the names?

Tropical cyclones are named by a世界气象组织委员会。以下是一个很好的页面,描述了热带气旋的命名,并提供了当前名称列表:
Worldwide Tropical Cyclone Names.

Do you have an older version of a data product?

When we update to a newer version of a data product we usually make significant improvements to the data. We therefore discourage using older versions. That said, if you need access to an older version for confirmation of a previous analysis, please联系我们.

我需要亮度温度数据。我在哪里可以从哪里得到?

Brightness temperatures are available for many of the microwave radiometers. We do not currently provide the files at RSS. They are available from some of the NASA DAACs and NOAA data centers. See the links in the Brightness TemperatureData Access Table.

什么是海洋学vs气象风向?

风directions are described as either "coming from" a direction (used by meteorologists) or "blowing to" a direction (used by oceanographers). The figure shows how we report the wind directions in our data products. This oceanographic convention means a 45 degree wind blows towards the northeast.Oceanographic Wind Direction Key

What is LTAN?

LTAN stands for Local Time of the Ascending Node and represents the time when the satellite crosses the equator when traveling from the south pole to the north pole (ascending). This time is the time of day at that Earth location when the satellite is overhead. For sun-synchronous orbiting satellites, this time is the same for each time zone (that is, a satellite with an LTAN of 6 am will be overhead at 6 am for every location on the equator each day.

What is a sun-synchronous orbit?

Sun-synchronous orbits combine the satellite’s altitude and inclination to allow measurement of the earth’s surface at the same local time in every time zone. A satellite in sun-synchronous orbit is typically located about 600-800 km above the earth’s surface. Most earth observation satellites used for climate purposes are in this low-earth orbit, in stark contrast with geostationary satellites typically used for short-term meteorological purposes, which orbit at nearly 36,000 km and have a much wider view of the earth’s surface. For more detailed information on orbit types, including images and a link to an animation, please see这里.

低频和中频风如何差异?

We produce two standard rain-free radiometer wind products: WSPD_LF (low-frequency) and WSPD_MF (medium frequency). The first, WSPD_LF is created using the frequency channels at 10.65 GHz and above (see tables above) and is most similar to the only wind offered in the version-5 AMSR-E data files or the first wind of the TMI files. The second, WSPD_MF, uses frequency channels at 18.7 GHz and above and is most similar to the SSM/I and SSMIS winds.
Each wind product has distinct advantages. The WSPD_LF is less affected by the atmosphere and rain, but is affected by 10.65 GHz RFI and sun glitter effects. The WSPD_MF has a higher effective spatial resolution, is less affected by ice and land contamination, and is only slightly affected by sun glitter effects and RFI. The WSPD_MF are a little noisier than the WSPD_LF.

“I saw this plot on a denialist web site. Is this really your data?”

We get this question quite a bit since many people use and look at our data to help them understand climate change. We encourage you to read more in the博客帖子containing a full explanation of Carl Mears' point of view on the RSS AMSU data and the differences with climate models used in the IPCC AR5 report.


如果您没有找到答案的答案,请联系我们. We aim to respond to support submissions within 2 - 3 business days.