Astrobiology Science and Technology for Exploring Planets (ASTEP)

2008 High Lakes Project: From Early Mars to Today’s Earth

October 15, 2008 / Written by: Lyn Bartlett

The highest volcanic lakes in the world are located in the Andes. Their elevation and isolation make them some of the least understood lakes on Earth and excellent analogs for martian lakes that existed 3.5 billion years ago. The NAI-funded High Lakes Project (HLP), led by PI Nathalie Cabrol, has been investigating the geophysical environment of high altitude lakes in the Central Andes of Bolivia and Chile since 2002 and they are gearing up to return this October.

On this trip, which begins on October 29th, Nathalie and her team will be collecting data to characterize the response of these lakes to climate variability in one of the best terrestrial environmental analogs to early Mars. No location on Earth can be defined as a perfect analog to Mars but many of the important parameters sought for to model early Mars are present in the Bolivian and Chilean altiplano. Because of the altitude and latitude of the studied sites, many of the parameters similar to ancient Mars are present together, including low average temperature, high-daily temperature variations (-40˚C / +10˚C), thin atmosphere (480 – 600 mb), high solar irradiance (170% sea level), ice, reduced yearly precipitation, volcanic and hydrothermal environment. The unique value of the area as a Mars analog was recognized in 2003 by NASA, which awarded Nathalie a five year grant (the High Lakes Project, HLP) through the NASA Astrobiology Institute to characterize the ecology of UV radiation in several lakes shown in Table 1.

Table 1 – Lake localization and characteristics

The central objective of the 2008 expedition will be to document the impact of rapid climate change on these lakes and their ability to sustain life in a highly dynamic environment. The altiplano is one of the “hot spots” of Global Warming and its effects, such as loss of precipitation (50% in 50 years in some parts), glacier retreat, increased impact of UV radiation in bodies of water that evaporate, are very similar to what Mars might have experienced about 3.5 billion years ago. In doing so, the project does not only address the question about early Mars water, habitability, and life, it also documents a subject of critical importance on Earth right now: How water resources and life are responding to the climate change Earth is experiencing today? On one hand, studying them allows us to better prepare future missions to Mars that will focus on searching for traces of life (whether past or present). On the other hand, understanding the response of these lakes and life adaptation (or lack thereof) to rapid changes may hold important clues to forecast the evolution of other threatened terrestrial lakes, and possibly help find solutions to Global Warming by identifying and quantifying the issues.