LEXPLORE PLATFORM

LéXPLORE Letters No. 43

This newsletter was generated on the 09-04-2024.

The figures below are showing data for the period 19-03-2024 to 02-04-2024.

Until today, Thetis sampled 4215 depth profiles on Lake Geneva. In this Newsletter we show 30 profiles, so just 0.71% of the recorded data. The complete data set is available at Datalakes.

Data highlights of this issue

Everything is still on fire. Lake Geneva below our platform is still much too warm for this time of the year, with substantial positive anomalies throughout the whole water column.

The lake heating was shortly interrupted by a windy, cold front passing by on March 23rd to 25th. With waves up to 80 cm and temperatures dropping below 4° Celcius, the water column was violently shuffled and cooled down. This striking event can be seen in the temperature, oxygen, Chorophyll A and backscattering plots. That said, it created merely a dent in the temperature anomalies, meaning this rather “cold” atmospheric event just barely turned water temperatures to average for a day or two.

This event also completely removed any accumulation of Chlorophyll A below the platform and with the continuous windy conditions, negative Chlorophyll A anomalies prevail for the rest of our two week snapshot.

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, 43, https://lexplore.info/wp-content/uploads/2024/04/lexplore-letters-2024-04-09.html