LEXPLORE PLATFORM

LéXPLORE Letters No. 7

This newsletter was generated on the 22-11-2022.

The figures below are showing data for the period 01-11-2022 to 15-11-2022.

Until today, Thetis sampled 3099 depth profiles on Lake Geneva. In this Newsletter we show 52 profiles, so just 1.68% of the recorded data. The complete data set is available at Datalakes.

Data highlights of this issue

While the salinity and conductivity sensors are under maintenance, we are happy to report that the new rain gauge on our automatic weather station is now live and included in this and future issues. Since the temporal resolution is very high for our weather data, you might need to zoom in a bit to discover the blue bars. But we promise they are there. We will experiment with the visualisation of that variable and what works the best going into the future. We further exchange the salinity plot for chlorophyll anomalies, showing you when and where we have more phytoplankton than usual.

From the displayed data, we see a slow return to normal lake water temperature conditions, with air temperatures dropping ever so slightly. Nevertheless, the upper lake levels are still quite a bit too warm. We see at least two atmospheric fronts and their storms passing by the platform, with elevated wind speeds, wave heights and precipitation. Those events mixed the lake down to 35 meters and pushed low oxygen water up while distributing heat further down the water column.

What is displayed

Data from the Thetis profiler:

  • Water Temperature in °Celsius

  • Water Temperature Anomaly on daily esolution with respect to to the available daily climatology from Thetis so far in Kelvin

  • Dissolved Oxygen mg/L

  • Oxygen Saturation in %

  • Chlorophyll A in μg/L

  • Chlorophyll A Anomaly on daily esolution with respect to to the available daily climatology from Thetis so far in μg/L

  • Backscattering of light 700 nm in 1.e-2 m-1, representing zooplankton or larger particles in the water

Data from the automatic weather station:

  • Air Temperature in °Celsius

  • Wind Speend in m/s

  • Precipitation in mm

Data from the wave buoy:

  • Wave height in decimeter

Authorship and further information

This newsletter is created by EPFL, specifically Martin Wegmann.

For more information about LéXPLORE, contacting us and possibilities to visit the platform: lexplore.info

If you want to know more about the Chlorophyll distribution across Lake Geneva, have a look at the satellite data map by our colleagues at CIPEL.

If you want to know more about the water temperature distribution across Lake Geneva, have a look at the lake reanalysis and forecasts by our colleagues at EAWAG.

If you want to use figures from the LéXPLORE Letters, you can use the following citation:

EPFL, Limnology Center 2022: LéXPLORE Letters, 7, https://lexplore.info/wp-content/uploads/2022/11/lexplore-letters-2022-11-22.html