LEXPLORE PLATFORM

LéXPLORE Letters No. 46

This newsletter was generated on the 21-05-2024.

The figures below are showing data for the period 30-04-2024 to 14-05-2024.

Until today, Thetis sampled 4327 depth profiles on Lake Geneva. In this Newsletter we show 58 profiles, so just 1.34% of the recorded data. The complete data set is available at Datalakes.

Data highlights of this issue

After a cold end of April, air temperatures went up to 20° Celsius in the first half of May. These atmospheric conditions are reflected in a sharp rise of surface water temperatures around May 12th. This is also when the negative surface water temperature anomalies are dissolving and the sign of the gradient between surface and deeper layer temperature anomalies is reversing.

We do however find that Chlorophyll A concentrations are still well below previous years. The windy, rainy and cold conditions (cold relative to previously recorded springs) did prevent a substantial build-up of phytoplankton communities. On the flip side, these conditions continuously shuffled thermal energy into the deeper lake levels, which is visible in the positive temperature anomalies for this time of year.

What is displayed

Data from the Thetis profiler:

  • Water Temperature in °Celsius

  • Water Temperature Anomaly on daily resolution 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 resolution 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 Speed 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 2024: LéXPLORE Letters, 46, https://lexplore.info/wp-content/uploads/2024/05/lexplore-letters-2024-05-21.html