Evidence of Climate Change Based on Lake Surface Temperature Trends in South Central Chile

Arnaldo Aranda,José Arumí-Ribera,Daniela Rivera-Ruiz,Lien Rodríguez-López,Pablo Pedreros,Luis Morales-Salinas,Guillermo Fuentes-Jaque,Roberto Urrutia

doi:10.3390/rs13224535

Abstract

Lake temperature has proven to act as a good indicator of climate variability and change. Thus, a surface temperature analysis at different temporal scales is important, as this parameter influences the physical, chemical, and biological cycles of lakes. Here, we analyze monthly, seasonal, and annual surface temperature trends in south central Chilean lakes during the 2000–2016 period, using MODIS satellite imagery. To this end, 14 lakes with a surface area greater than 10 km2 were examined. Results show that 12 of the 14 lakes presented a statistically significant increase in surface temperature, with a rate of 0.10 °C/decade (0.01 °C/year) over the period. Furthermore, some of the lakes in the study present a significant upward trend in surface temperature, especially in spring, summer, and winter. In general, a significant increase in surface water temperature was found in lakes located at higher altitudes, such as Maule, Laja and Galletué lakes. These results contribute to the provision of useful data on Chilean lakes for managers and policymakers.

Highlights

Inland water ecosystems provide multiple ecosystem services and are vital for human consumption, irrigation, sanitation, transportation, recreation, culture, and industry [1].In recent decades, these ecosystems have experienced high stress from various human impacts as well as climate change [2,3]
Not all the lakes had an equal number of in situ data, the results show a high correlation between Moderate Resolution Imaging Spectroradiometer (MODIS) lake surface water temperature (LSWT) and in situ LSWT, with an R2 coefficient ranging from 0.85 to 0.94 for six of the 14 lakes analyzed in this study (Table 2)
The results suggest that the processing of MODIS LSWT images and a larger dataset, and a greater temporal resolution, might be a better alternative for future observations

Summary

Introduction

Inland water ecosystems provide multiple ecosystem services and are vital for human consumption, irrigation, sanitation, transportation, recreation, culture, and industry [1]. In recent decades, these ecosystems have experienced high stress from various human impacts as well as climate change [2,3]. The main results indicated that oxygen levels declined by 5.5% at the surface and that surface temperatures increased by 0.38 ◦ C/decade [9] These studies have mainly used data records from the Northern Hemisphere; there are fewer observational records or satellite-based studies related to LSWT trends in the Southern Hemisphere, such that they are less well understood than LSWT trends in Northern Hemisphere lakes

Methods

Results

Conclusion