On the dynamic forcing of short-term climate fluctuations by feedback mechanisms

• Main Author: Reiter, E.R.
• Language: unknown
• Published: 2013
• Subjects: 54 ENVIRONMENTAL SCIENCES; CLIMATES; VARIATIONS; ATLANTIC OCEAN; DATA COMPILATION; EARTH ATMOSPHERE; ENERGY TRANSFER; FEEDBACK; FOURIER ANALYSIS; GRAPHS; HEAT TRANSFER; HYDROLOGY; PACIFIC OCEAN; RAIN; SEAS; SURFACE WATERS; SURGES; TEMPERATURE MEASUREMENT; WATER CURRENTS; WIND; ATMOSPHERIC PRECIPITATIONS; CURRENTS; DATA; DATA FORMS; INFORMATION; NUMERICAL DATA; Pacific; North Atlantic
• Online Access: http://www.osti.gov/servlets/purl/5639705; https://www.osti.gov/biblio/5639705; https://doi.org/10.2172/5639705

The energies involved in the general circulation of the atmosphere, especially the zonal available potential energy, show considerable interannual variability, suggesting the presence of various internal feedback mechanisms in the ocean-atmosphere system. Sea-surface temperature (SST) variations appear to have some effect on the hydrological cycle. The possible existence of feedback mechanisms between ocean and atmosphere seem to be evident in some of the data from the North Pacific and North Atlantic. One of these proposed mechanisms involves the variation in the convergence between the North and South Pacific trade-wind systems and is strongly reflected in rainfall variability within the dry region of the equatorial Pacific. Similar variations appear in low-latitude SST anomalies. The convergence between the two trade-wind systems in the Atlantic region also undergoes marked interannual variations. This quasi-biennial oscillation (QBO) in trade-wind convergence over the Atlantic appears to be tied to the global QBO of equatorial stratospheric winds and to regional rainfall regimes in the dry region of northeastern Brazil. A variability pattern of SST's with a QBO has been detected off the coast of Senegal, in the Gulf of Guinea and even in the Gulf Stream as it leaves the North American continental shelf. Possible physical connections between some of these QBO's are pointed out by a hypothetical feedback model. It is also suggested that interaction of a QBO with the annual cycle may lead to beating frequencies resembling climatic trends of a duration of several years.