Humans are strongly affected by climate and temperature. Studies show that colder environments foster cognitive performance. Colzato and Sellaro found that working memory can be enhanced by performing under the preferred, not the objective temperature.
Sellaro, R., Hommel, B., Manai, M., and Colzato, L.S. (2014). Preferred, but not objective temperature predicts working memory depletion. Psychological Research. DOI 10.1007/s00426-014-0558-4