Reverse transcriptase is characteristic of retroviruses, including HIV (human immunodeficiency virus), the virus responsible for AIDS (acquired immunodeficiency syndrome). All retroviruses encode a polymerase enzyme in their pol gene that is both necessary and sufficient for the replication of their RNA genomes.
PDO positive phase global pattern. The Pacific Decadal Oscillation (PDO) is a robust, recurring pattern of ocean-atmosphere climate variability centered over the mid-latitude Pacific basin.
ENSO is the El NiÃ±o-Southern Oscillation, the name scientists use for what is often called El NiÃ±o. The Southern Oscillation is a see-saw shift in surface air pressure between the eastern and western halves of the Pacific. When pressure rises in the east, it falls in the west and vice versa.