Three American graduate students, Michael McGlue and Mark Trees (University of Arizona), and Kelly Wendt (University of Minnesota), working with two Brazilian colleagues, Aguinaldo Silva and Fabricio Corradini (Universidade Federal de Mato Grosso do Sul ) were arrested on June 17, while doing paleoclimate and environmental change field work in the Pantanal, north of Corumba. This research project has investigated how changing climate conditions in the recent geological past have affected the Pantanal ecosystem, which is world famous as one of the Earth’s largest wetlands. The University of Arizona research team, under the direction of Professor Andrew Cohen and in collaboration with Professor Mario Assine of UNESP does this research by collecting short sediment cores (less than a few meters long) from the bottom of lakes and wetlands in the Pantanal region. The cores provide records of past climate as particles sensitive to climate change settle to the bottom of the lake. Lake and wetland deposits are well known for their ability to provide detailed information about global warming and other aspects of environmental change.
 
Since its inception the project has offered an opportunity for Brazilian and American scientists to work together and obtain important training on climate and environmental research methods. Two UNESP scientists spent 3 months at the University of Arizona in 2008 working on this project in Tucson and taking advantage of University of Arizona facilities for the collaborative effort, and University of Arizona scientists have made several visits to the Pantanal with the Brazilian team.
 
The five researchers were initially arrested and charged with Article 2nd, paragraph 1st, law#8176/91 and Articles 44 and 55, law 9605/98, charges primarily related to the extraction of mineral resources and permit violations. The charge that these researchers were involved in minerals or natural resource exploitation of any kind is simply untrue-the sediment cores are only collected to interpret signals of environmental change such as global warming and its effect on the Pantanal region. The students were working in good faith under and collaborating with Brazilian scientists at the time of their arrests. The University of Arizona and the students each believed that all of the necessary Brazilian research permits were in place to authorize the research. The Brazilian environment, and especially the Pantanal region benefits greatly from this type of environmental research from sediment cores, since it gives clear signals of how such changes have affected and will affect the region in the future.  
 
We the undersigned understand why the authorities initially may have questioned the legality and appropriateness of what the researchers were doing.  But with a clear understanding of the beneficial nature of this research program, we urge the authorities to treat this issue as a simple misunderstanding on the researcher’s part of permit requirements. We respectfully request that the American students be permitted to return to the United States as soon as possible to continue their education and research and rejoin their families and friends.