Atlantic multidecadal oscillation AMO spatial pattern. Atlantic Multidecadal Oscillation index computed as the linearly detrended North Atlantic sea surface temperature anomalies 1856-2009. The Atlantic Multidecadal Oscillation (AMO) is a mode of variability occurring in the North Atlantic Ocean and which has its principal expression in the sea surface temperature (SST) field. Definition[edit] The Atlantic multidecadal oscillation (AMO) was identified by Schlesinger and Ramankutty in 1994.[2] The AMO signal is usually defined from the patterns of SST variability in the North Atlantic once any linear trend has been removed. Atlantic Multidecadal Oscillation according to the methodology proposed by van Oldenborgh et al. Several methods have been proposed to remove the global trend and ENSO influence over the North Atlantic SST. Ting et al. however argue that the forced SST pattern is not spatially uniform; they separated the forced and internally generated variability using signal to noise maximizing EOF analysis.[1]
El Niño–Southern Oscillation "El Nina" redirects here. It is not to be confused with La Niña. The 1997–98 El Niño observed by TOPEX/Poseidon. The white areas off the Tropical Western coasts of northern South and all Central America as well as along the Central-eastern equatorial and Southeastern Pacific Ocean indicate the pool of warm water.[1] El Niño is the warm phase of the El Niño Southern Oscillation (commonly called ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (between approximately the International Date Line and 120°W), including off the Pacific coast of South America. El Niño Southern Oscillation refers to the cycle of warm and cold temperatures, as measured by sea surface temperature, SST, of the tropical central and eastern Pacific Ocean. Developing countries dependent upon agriculture and fishing, particularly those bordering the Pacific Ocean, are the most affected. Definition[edit] Effects of ENSO warm phase (El Niño)[edit]
Sea surface temperature This graph shows how the average surface temperature of the world's oceans has changed since 1880. This graph uses the 1971 to 2000 average as a baseline for depicting change. Choosing a different baseline period would not change the shape of the data over time. The shaded band shows the range of uncertainty in the data, based on the number of measurements collected and the precision of the methods used. Sea surface temperature increased over the 20th century and continues to rise. This is a daily, global Sea Surface Temperature (SST) data set produced on December 20th, 2013 at 1-km (also known as ultra-high resolution) by the JPL ROMS (Regional Ocean Modeling System) group Weekly average sea surface temperature for the World Ocean during the first week of February 2011, during a period of La Niña. Sea surface temperature and flows. Sea surface temperature (SST) is the water temperature close to the ocean's surface. Measurement[edit] Thermometers[edit] Weather satellites[edit] See also[edit]
Solubility pump Air-sea exchange of CO2 In oceanic biogeochemistry, the solubility pump is a physico-chemical process that transports carbon (as dissolved inorganic carbon) from the ocean's surface to its interior. Overview[edit] The solubility pump is driven by the coincidence of two processes in the ocean : The solubility of carbon dioxide is a strong inverse function of seawater temperature (i.e. solubility is greater in cooler water)The thermohaline circulation is driven by the formation of deep water at high latitudes where seawater is usually cooler and denser Since deep water (that is, seawater in the ocean's interior) is formed under the same surface conditions that promote carbon dioxide solubility, it contains a higher concentration of dissolved inorganic carbon than one might otherwise expect. One consequence of this is that when deep water upwells in warmer, equatorial latitudes, it strongly outgasses carbon dioxide to the atmosphere because of the reduced solubility of the gas. CO2 (aq) + H2O
Continental shelf pump In oceanic biogeochemistry, the continental shelf pump is proposed to operate in the shallow waters of the continental shelves, acting as a mechanism to transport carbon (as either dissolved or particulate material) from surface waters to the interior of the adjacent deep ocean.[1] Overview[edit] Originally formulated by Tsunogai et al. (1999),[1] the pump is believed to occur where the solubility and biological pumps interact with a local hydrography that feeds dense water from the shelf floor into sub-surface (at least subthermocline) waters in the neighbouring deep ocean. Tsunogai et al.' Significance[edit] Based on their measurements of the CO2 flux over the East China Sea (35 g C m−2 y−1), Tsunogai et al. (1999)[1] estimated that the continental shelf pump could be responsible for an air-to-sea flux of approximately 1 Gt C y−1 over the world's shelf areas. References[edit] Rippeth TP, Scourse JD, Uehara, K (2008). ^ Jump up to: a b c d e Tsunogai, S.; Watanabe, S.; Sato, T. (1999).
Biological pump Air-sea exchange of CO2 The biological pump, in its simplest form, is the ocean’s biologically driven sequestration of carbon from the atmosphere to the deep sea.[1] It is the part of the oceanic carbon cycle responsible for the cycling of organic matter formed by phytoplankton during photosynthesis (soft-tissue pump), as well as the cycling of calcium carbonate (CaCO3) formed by certain plankton and mollusks as a protective coating (carbonate pump). Overview[edit] The biological pump can be divided into three distinct phases,[2] the first of which is the production of fixed carbon by planktonic phototrophs in the euphotic (Sunlit) surface region of the ocean. Once this carbon is fixed into soft or hard tissue, the organisms either stay in the euphotic zone to be recycled as part of the regenerative nutrient cycle or once they die, continue to the second phase of the biological pump and begin to sink to the ocean floor. Primary Production[edit] CO2 + H2O + light → CH2O + O2 See also[edit]
Carbonate compensation depth Calcite compensation depth (CCD) is the depth in the oceans below which the rate of supply of calcite (calcium carbonate) lags behind the rate of solvation, such that no calcite is preserved. Aragonite compensation depth (hence ACD) describes the same behaviour in reference to aragonitic carbonates. Aragonite is more soluble than calcite, so the aragonite compensation depth is generally shallower than the calcite compensation depth. Calcium carbonate is essentially insoluble in sea surface waters today. Calcareous plankton and sediment particles can be found in the water column above the CCD. Variations in value of the CCD[edit] The exact value of the CCD depends on the solubility of calcium carbonate which is determined by temperature, pressure and the chemical composition of the water - in particular the amount of dissolved CO2 in the water. In the geological past the depth of the CCD has shown significant variation. See also[edit] References[edit]
Global Ocean Data Analysis Project The Global Ocean Data Analysis Project (GLODAP) is a synthesis project bringing together oceanographic data collected during the 1990s by research cruises on the World Ocean Circulation Experiment (WOCE), Joint Global Ocean Flux Study (JGOFS) and Ocean-Atmosphere Exchange Study (OACES) programmes. The central goal of GLODAP is to generate a global climatology of the World Ocean's carbon cycle for use in studies of both its natural and anthropogenically-forced states. GLODAP is funded by the National Oceanic and Atmospheric Administration (NOAA), the U.S. Department of Energy (DOE), and the National Science Foundation (NSF). Dataset[edit] Additionally, analysis has attempted to separate natural from anthropogenic DIC, to produce fields of pre-industrial (18th century) DIC and "present day" anthropogenic CO2. Gallery[edit] The following panels show sea surface concentrations of the fields prepared by GLODAP. See also[edit] References[edit] External links[edit] GLODAP website
Ocean acidification NOAA provides evidence for upwelling of corrosive "acidified" water onto the Continental Shelf. In the figure above, note the vertical sections of (A) temperature, (B) aragonite saturation, (C) pH, (D) DIC, and (E) pCO2 on transect line 5 off Pt. St. George, California. The potential density surfaces are superimposed on the temperature section. The 26.2 potential density surface delineates the location of the first instance in which the undersaturated water is upwelled from depths of 150 to 200 m onto the shelf and outcropping at the surface near the coast. Ocean acidification is the ongoing decrease in the pH of the Earth's oceans, caused by the uptake of carbon dioxide (CO2) from the atmosphere.[2] An estimated 30–40% of the carbon dioxide released by humans into the atmosphere dissolves into oceans, rivers and lakes.[3][4] To achieve chemical equilibrium, some of it reacts with the water to form carbonic acid. Ocean acidification has occurred previously in Earth's history.