NASA's Phoenix spacecraft landed in the northern polar region of Mars Sunday, May 25, 2008, to begin three months of examining a site chosen for its likelihood of having frozen water within reach of the lander's robotic arm. (UPI Photo/NASA, JPL-Caltech, University of Arizona)

The University of California-Berkeley-led researchers said they used Martian soil analyses made by National Aeronautics and Space Administration spacecraft between 1976 and 2006.

"By analyzing the chemistry of the planet's soil, we can derive important information about Mars' climate history," said Professor Ronald Amundson, the study's lead author. "The dominant view … is that the chemistry of Mars soils is a mix of dust and rock that has accumulated over the eons, combined with impacts of upwelling groundwater, which is almost the exact opposite of any common process that forms soil on Earth.

"In this paper, we try to steer the discussion back by re-evaluating the Mars data using geological and hydrological principles that exist on Earth," he said.

While the study does not delve directly into evidence of life on Mars, the researchers said it does suggest what kind of climate such life, if it existed, might have encountered.

The study is to appear in the August issue of Geochimica et Cosmochimica Acta, the journal of the International Geochemical Society.