New article: Warming trends of perialpine lakes from homogenised time series of historical satellite and in-situ data

New research article about warming trends of perialpine lakes obtained from homogenised time series of historical satellite and in-situ data

Pareeth, S., Bresciani, M., Buzzi, F., Leoni, B., Lepori, F., Ludovisi, A., Morabito, G., Adrian, R., Neteler, M., Salmaso, N., 2017. Warming trends of perialpine lakes from homogenised time series of historical satellite and in-situ data. Science of The Total Environment 578, 417–426. doi:10.1016/j.scitotenv.2016.10.199

Abstract

The availability of more than thirty years of historical satellite data is a valuable source which could be used as an alternative to the sparse in-situ data. We developed a new homogenised time series of daily day time Lake Surface Water Temperature (LSWT) over the last thirty years (1986–2015) at a spatial resolution of 1 km from thirteen polar orbiting satellites. The new homogenisation procedure implemented in this study corrects for the different acquisition times of the satellites standardizing the derived LSWT to 12:00 UTC. In this study, we developed new time series of LSWT for five large lakes in Italy and evaluated the product with in-situ data from the respective lakes. Furthermore, we estimated the long-term annual and summer trends, the temporal coherence of mean LSWT between the lakes, and studied the intra-annual variations and long-term trends from the newly developed LSWT time series. We found a regional warming trend at a rate of 0.017 °C yr −1 annually and 0.032 °C yr −1 during summer. Mean annual and summer LSWT temporal patterns in these lakes were found to be highly coherent. Amidst the reported rapid warming of lakes globally, it is important to understand the long-term variations of surface temperature at a regional scale. This study contributes a new method to derive long-term accurate LSWT for lakes with sparse in-situ data thereby facilitating understanding of regional level changes in lake’s surface temperature.

Highlights

  • Lake surface temperature responds rapidly to climate change.
  • A new satellite derived daily LSWT time series (1986–2015) is developed.
  • Rapid warming during summer is reported for the perialpine lakes in Italy.
  • High temporal coherence between summer and annual LSWT means is reported.
  • The method is reproducible and extensible to other lakes globally.

Article: doi:10.1016/j.scitotenv.2016.10.199