Best wishes for 2017 !


Bonne année !

A fifth season starts for the "Time series" blog (2016 stats are provided at the end of the post) ! We wish to all our readers that 2017 :

  • will be very happy, exciting, in a good shape, in a peaceful context,
  • with a lot of blue skies and nice satellite images abbove your sites,
  • with a successful launch of Sentinel-2B et a fully operational system,
  • with (really, even if it's hard to believe) Venµs launch and images every second day on 100 sites,
  • with a Muscate ground segment that produces lots of Sentinel-2 L2A data (production start was slow and unstable, but it seems the reason was found and corrected),
  • with new products at Theia : a Snow cover product, and land cover maps of France
  • hopefully with powerful new public cloud servers, to process the data next to them, and avoid downloads and data duplications, in an open source way, and not under private APIs
  • with a new French government, that will increase again public research budgets and will not decrease the number of civiil servants, that make this blog exist
  • and a new American government, that will NOT fulfill its commitments, and among other things, will not come back to data protectionism.  The openness of Landsat or Sentinel data is a game changer for remote sensing, and makes our work really useful.


Sequence of two Landsat-8 and Sentinel-2A images. Both images are level 1 product displayed as natural color composites. Click to enlarge.

2016 Blog stats

2013 2014 2015 2016
Number of visits 13985 22928 34723 47773
Number of pages read 30922 46940 66947 89555

2016 was a new year of exponential increase of the blog audience, thanks to a lot of new authors :

  • Simon Gascoin scores of nice posts, and especially the saga around the glacier avalanches in Tibet, or how this blog  (and the Sentinel satellites) nearly saved lives (yes, really !)
  • the posts on water and agriculture from Florian Helen, Michel Le Page, Marjorie Battude and Isabelle Soleihavoup,
  • the first land cover maps over the whole France automatically produced from Landsat data, released by Jordi Inglada and his team.
  • the results from Pierre Alexis Herrault in Siberia (it was not a punishment) on dissolved organic matter in the rivers, or on forest fires
  • the discussions on google earth engine, and the associated risks
  • the demonstration of Sentinel-2 like data capacity to recognize tree species (from David Sheeren)
  • the nice results from MACCS, and the difficult start of MUSCATE ( but now, it seems to work at full speed)
  • we would have liked to get news from the microwaves team at CESBIO, but they seemto be a little shy

This blog is open to new authors, writing a post can be done quickly (especially the second and third ones...), and you don't even need to be part of CESBIO to contribute.


Here is the ranking of the most frequently read pages :


A python module for batch download of Sentinel data from ESA 2190
Sentinel-2-download 1451
Mapping flooded areas using Sentinel-1 in Google Earth Engine 1349
Sentinel-2 captures the coastal ground uplift after Kaikoura earthquake in New Zealand 1333
L’ortho-rectification, comment ça marche ? 1063
La production de cartes d’occupation du sol, comment ça marche? 1061
S2 tiles produced to L2A by THEIA 1037
MACCS, how it works 828
How to automatically download Sentinel data from PEPS collaborative ground segment 798
Scientists anticipate another glacier collapse in Tibet from satellite data 778
Sentinel-2A captures a giant ice avalanche in Tibet 747
USGS now delivers atmospherically corrected LANDSAT data 723
Landsat-download 705
Theia diffuse les données de niveau 2A de Sentinel-2 sur la France 697
A python module for batch downloads of LANDSAT data. 652
The cloud detection : how it works. 612
Sentinel-2 Agriculture 610
The Sentinel-2 tiles, how they work ? 601
First comparison of Sentinel-2 cloud masks delivered by MACCS and SEN2COR 573
High spatial and temporal resolution optical remote sensing data to estimate maize biomass and yield 503


What may we conclude from that ?

  • distributing small open source codes gets a large success (and a lot of questions every week...)
  • crowds come to read the geophysical findings of Simon Gascoin (with a lot of advertising on social networks)
  • the use case of GEE yields much more connections than the posts that warn you about the risks
  • the "how it works" series are still succesful
  • the 20th entry of the ranking really fascinated a German reader from Berlin with 400 connections
  • the suspense about Theia's production is still followed

Posted under: En Français, Landsat, Sentinel-2, THEIA, Venµs

One comment

  • Saba on 15/01/2017 at 02:53 said:

    Dear Professor Hagolle,
    I read your paper called “A Multi-Temporal and Multi-Spectral Method to Estimate Aerosol Optical Thickness over Land, for the Atmospheric Correction of FormoSat-2, Landsat, VENμS and Sentinel-2 Images”. I want to derive AOD over a lake from Landsat 7. I want to use dark target “MS” algorithm.
    I was wondering if I can follow dark target algorithm over ocean developed by NASA for MODIS project.
    Also, as this algorithm assumed that reflectance at 660 nm over the ocean is almost zero, I was thinking that I can discard the atmospheric correction in this case?


Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>