LEXPLORE PLATFORM

LéXPLORE Letters No. 1

This newsletter was generated on the 29-08-2022.

The figures below are showing data for the period 08-08-2022 to 22-08-2022.

Until today, Thetis sampled 2862 depth profiles on Lake Geneva. In this Newsletter we show 68 profiles, so just 0.02% of the recorded data. The complete data set is available at Datalakes.

Data highlights of this issue

As we can see from the temperature anomalies, the upper lake levels are still warmer than measured in previous years. Chlorophyll maxima occur relatively deep with low concentrations, even though plenty of sunlight and heat is available. This is probably due to low nutrient availability in the upper levels.

We see oxygen maxima naturally occuring above the phytoplankton maxima, with phytoplankton migrating upwards in the second week due to mixing of the lake, precipitation and runoff events, bringing nutrients to the surface. The mixing is triggered by summer storms passing through on the 14th and 17th of August. These storms also freshened up the surface water layers.

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 °Celsius

  • Dissolved Oxygen mg/L

  • Oxygen Saturation in %

  • Chlorophyll A in μg/L

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

  • Salinity in mg/L

Data from the automatic weather station:

  • Air Temperature in °Celsius

  • Wind Speend in m/s

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, 1, https://lexplore.info/wp-content/uploads/2022/08/lexplore-letters-2022-08-29.html