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This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 7 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 3 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 1 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 8 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 10 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 9 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 12 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 11 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 13 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 15 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 17 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 16 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 18 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 19 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 9 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
This release note discusses the science data products produced by the Science Processing Operations Center at Ames Research Center from Sector 20 observations made with the TESS spacecraft and cameras as a means to document instrument performance and data characteristics.
We use a spectral-based approach that employs principal component analysis along with a relatively shallow artificial neural network (NN) to substantially reduce noise and other artifacts in terrestrial chlorophyll solar-induced fluorescence (SIF) retrievals. SIF is a very small emission at red and far-red wavelengths that is difficult to measure and is highly sensitive to random errors and systematic artifacts. Our approach relies upon an assumption that a trained NN can effectively reconstruct the total SIF signal from a relatively small number of leading principal components of the satellite-observed far-red radiance spectra without using information from the trailing modes that contain most of the random errors. We test the approach with simulated reflectance spectra produced with a full atmospheric and surface radiative transfer model using different observing and geophysical parameters and various noise levels. Resulting noisy and noise-reduced retrieved SIF values are compared with true values to assess performance. We then apply our noise reduction approach to SIF derived from two different satellite spectrometers. For evaluation, since the truth in this case is unknown, we compare SIF retrievals from two independent sensors with each other. We also compare the noise-reduced SIF temporal variations with those from an independent gross primary product (GPP) product that should display similar variations. Results show that our noise reduction approach improves capture of SIF seasonal and inter-annual variability. Our approach should be applicable to many noisy data products derived from spectral measurements. Our methodology does not replace the original retrieval algorithms; rather the original noisy retrievals are needed as the target for the NN training process.
SMAP mission was launched on 31st January 2015 in a 6 AM 6 PM sun-synchronous orbit at 685 km altitude to measure soil moisture and freethaw globally. The passive instrument of SMAP is a fully polarimetric L-band radiometer (1.4GHz) operating with a bandwidth of 24MHz. The radiometer L1B data product version 3 has been released for public science activities. Post-launch calibration and validation activities are described in [4,5]. Validation results show that SMAP antenna temperature (TA) is 2.6 K warmer over galactic Cold Sky (CS), and land TB is 2.6 K colder comparing to SMOS land TB (compared at the top of the atmosphere) after the update of the reflectors thermal model. Due to the biases, the SMAP radiometer is under re-calibration for next data release in 2018.We present the updated calibration approaches for the SMAP radiometer product. We will discuss the various radiometer calibration parameters and part of the validation process and result.