Köppen climate classification
The Köppen climate classification divides climates into five main climate groups, with each group being divided based on seasonal precipitation and temperature patterns. The five main groups are "A" (tropical), "B" (dry), "C" (temperate), "D" (continental), and "E" (polar). Each group and subgroup is represented by a letter. All climates are assigned a main group (the first letter). All climates except for those in the "E" group are assigned a seasonal precipitation subgroup (the second letter). For example, "Af" indicates a tropical rainforest climate. The system assigns a temperature subgroup for all groups other than those in the "A" group, indicated by the third letter for climates in "B", "C", and "D", and the second letter for climates in "E". For example, "Cfb" indicates an oceanic climate with warm summers as indicated by the ending "b". Climates are classified based on specific criteria unique to each climate type.
Continental climate
In the Koppen climate system, these climates grade off toward temperate climates equator-ward where winters are less severe and semi-arid climates where precipitation becomes inadequate for tall-grass prairies. In Europe these climates may grade off into oceanic climates in which the influence of cool oceanic air masses is more marked toward the west. The subarctic climate (Köppen: Dfc), with very cold, long and dry winters, but with at least one month above , might be considered a sub-type of the continental climate.While there are no major cities in South America that fall in to the classification of a continental climate, there are some remote places that have this climate. Due to the influence of the Ocean, Patagonia, including cities such as Punta Arenas, Chile and Ushuaia, Argentina, have an average winter temperature above 0°C, and so are classified as an oceanic climate.