Time series data for lake and hot spring chemistry, levels and temperature is available through FITS
When volcanic craters cool down after major eruptions, they often fill with water to form crater lakes. Some are cool, just filled by rain water, while others are warm or hot and remain connected to the volcanic plumbing. The colour of crater lakes and hots springs varies markedly according to the temperature and chemistry of the water, and the type and concentration of particles suspended within it.
The following measurements are recorded at crater lakes. Not all observations are available from each lake.
For more information on monitoring volcanoes see the volcano information page.