The Interannual Variability of Sea Surface Temperature in the Red Sea From 35 Years of Satellite and In Situ Observations. Issue 8 (21st August 2018)

• Record Type: Journal Article
• Authors: Karnauskas, Kristopher B.; Jones, Burton H.
• Is Part Of: Journal of geophysical research. Volume 123:Issue 8(2018)
• Page Start: 5824
• Page End: 5841
• Publication Date: 2018-08-21
• Subjects: Red Sea -- SST -- interannual -- observations -- satellite; Oceanography -- Periodicals; 551.4605
• DOI: 10.1029/2017JC013320
• Languages: English
• ISSNs: 2169-9275

Abstract

Abstract: Falling between the dynamics of the seasonal cycle and expressions of longer‐term trends, the interannual variability of sea surface temperature (SST) in the Red Sea has not received enough attention. With multiple decades of satellite SST observations with spatial resolution capable of resolving patterns of variability within the Red Sea, the time has come for a description and diagnosis of the observed interannual variability of SST in this important semienclosed sea. While interannual variability of SST occurs throughout the Red Sea in both summer and winter, the greatest variability is found in the northern Red Sea during winter. Objective analysis reveals two dominant statistical modes of interannual variability of Red Sea SST: a whole‐sea mode described by general warm or cool anomalies throughout the Red Sea (∼60% of total variance), and a meridional gradient mode of opposing SST anomalies in the northern and southern Red Sea (∼20% of total variance). The warm phase of the whole‐sea mode corresponds to warm surface air temperature anomalies extending across the broader region and local surface wind anomalies opposite to the mean low‐level circulation. The whole‐sea mode is found to be a regional response to remote forcing by the East Atlantic/Western Russia (EAWR) pattern. The gradient mode, on the other hand, is a manifestation of superimposing (and statistically independent) remote impacts of El Niño‐Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO) whereby ENSO drives SST anomalies in the southern Red Sea and the NAO drives SST anomalies in the northern Red Sea. Plain Language Summary: The Red Sea is climatically, ecologically, and economically important. The temperature at the surface of a body of water is a reliable indicator of its climatic and ecological conditions, and is readily observable from ships and Earth‐orbiting satellites. Studying Red Sea temperature fluctuations from decades of such observations reveal what physical factors affect the temperature and currents within the Red Sea, both near and far. We found that the year‐to‐year fluctuations in Red Sea temperature are affected by three factors: (1) the air temperature of the Middle East region, (2) an arctic climate cycle called the North Atlantic Oscillation, and (3) a tropical climate cycle known as El Niño. These three factors cause temperature fluctuations in the Red Sea by affecting how much heat can be exchanged between the Red Sea and the atmosphere above. With this knowledge, it may be possible to predict Red Sea temperature fluctuations in advance, especially given that El Niño is predictable. Key Points: The interannual variability of sea surface temperature in the Red Sea is analyzed from 1982 to 2016 using a 28 km satellite/in situ product Variability is greatest in the northern Red Sea in wintertime; objective analysis reveals a whole‐sea mode and a meridional gradient mode Surface heat exchange is a dominant mechanism in both modes; El Niño (North Atlantic Oscillation) impacts the southern (northern) Red Sea