A few years only after its worst drought in 1,200 years (2011-2016), the drought returns to California. Lake Oroville is both a witness and a victim of the extreme hydro-meteorological variability in the Golden State. It provides water to « homes, farms, and industries in the San Francisco Bay area, the San Joaquin Valley and Southern […]
This post intends to answer a question about Sentinel-HR, that we have had quite often inside or outside CNES : Securing continuity in a critical timeseries requires user community foresight, Programme justification, 10 yrs Agency prep, and finances. Whilst Sentinel-HR may well be an excellent/valid idea, I’m left asking why certain Copernicus contributing missions couldn’t […]
=> If you are working with Sentinel2 products, you probably heard that ESA new geometric processing is active since 1st of April 2021. This new processing, based on the geometric refinement of viewing parameters with respect to a Global Reference Image (GRI), should bring absolute location error from 11 meters (95.5% of products) to better […]
=> Field work rarely goes without a few small hazards. In the case of our new ROSAS station, newly installed a month ago, the hazard unfortunately took the form of a farm machine hitting the mast while tilling the soil on April 15th. The base of the mast twisted under the impact, leaving the structure […]
The distribution of MAJA L2A processor, as an executable software, started in april 1997, but we started counting the number of downloads only since October 2017. The cumulative number of downloads just reached 2000 on April the 2nd 2021. It is on average 1.56 downloads per day, and more than 2 downloads per work day […]
=> Here is a frequently asked question : I noticed, in such L2A product processed by MAJA, that some pixels had negative reflectances, is it normal ? No, it should not happen, but the fact it happens is not entirely surprising, I will explain it below. Unlike negative reflectances, reflectances greater than one can exist, […]
These space engineers are fast and efficient ! Just a week after our ROSAS station in Lamasquère was erected, we already have the first BRDF measurements, the producing of which required also the processing of calibration sequences. This was done thanks to our colleagues at CNES from the service in charge of measurement physics […]
=> At last! We announced it in March 2020, and here it is, one year later! From lock-downs to constraints related to crops grow stages or soil wetness, we have been forced to postpone the operations several times. And finally, the ROSAS* Lamasquère (South-Western France) station sent its very first measurements on March 17, 2021. […]
In the last few months, several papers on Sentinel-2 cloud detection have been published by MDPI remote sensing journal. We found large errors or shortcomings on two of these papers, that should not have been allowed by the reviewers or editors. The third one is much better, even if we disagree with one of its […]