Ocean Acidification: The Other CO2 Problem. Learn more about Ocean Acidification: The Other CO2 Problem To learn more about the science behind the film, see a list of citations. ACID TEST, a film produced by NRDC, was made to raise awareness about the largely unknown problem of ocean acidification, which poses a fundamental challenge to life in the seas and the health of the entire planet.
Like global warming, ocean acidification stems from the increase of carbon dioxide in the earth’s atmosphere since the start of the Industrial Revolution. Leading scientific experts on the problem, many of whom appear in the film and the outtakes below, believe that it's possible to cut back on global warming pollution, improve the overall health and durability of our oceans, and prevent serious harm to our world, but only if action is taken quickly and decisively.
The film originally aired on Discovery Planet Green. Video Extras Acid Test mentioned in the Senate Sen. Acid Test Outtake: Coral Reefs Acid Test Outtake: Food Web Acid Test Outtake: Policy. Shutdown of thermohaline circulation. A summary of the path of the thermohaline circulation. Blue paths represent deep-water currents, while red paths represent surface currents A shutdown or slowdown of the thermohaline circulation is a postulated effect of global warming. Thermohaline circulation and fresh water[edit] The red end of the spectrum indicates slowing in this presentation of the trend of velocities derived from NASA Pathfinder altimeter data from May 1992 to June 2002. Source: NASA. Some even fear that global warming may be able to trigger the type of abrupt massive temperature shifts which occurred during the last glacial period: a series of Dansgaard-Oeschger events – rapid climate fluctuations – may be attributed to freshwater forcing at high latitude interrupting the THC.
Studies of the Florida Current suggest that the Gulf Stream weakens with cooling, being weakest (by ~10%) during the Little Ice Age.[13] Measurements in 2004, 2005, 2008 and 2010[edit] Bryden measurements reported late 2005[edit] 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. 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. Consequently, these two processes act together to pump carbon from the atmosphere into the ocean's interior.
The solubility pump has a biological counterpart known as the biological pump. CO2 (aq) + H2O. 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. Shells of dead calcareous plankton sinking to deeper waters are practically unaltered until reaching the lysocline where the solubility increases dramatically. By the time the CCD is reached all calcium carbonate has dissolved according to this equation: Calcareous plankton and sediment particles can be found in the water column above the CCD. Variations in value of the CCD[edit] In the geological past the depth of the CCD has shown significant variation.
See also[edit] References[edit] 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.'s (1999)[1] original work focused on the East China Sea, and the observation that, averaged over the year, its surface waters represented a sink for carbon dioxide. This observation was combined with others of the distribution of dissolved carbonate and alkalinity and explained as follows : Significance[edit] References[edit] Rippeth TP, Scourse JD, Uehara, K (2008). See also[edit] 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. In these surface waters, phytoplankton use carbon dioxide (CO2), nitrogen (N), phosphorus (P), and other trace elements (barium, iron, zinc, etc.) during photosynthesis to make carbohydrates, lipids, and proteins. Primary Production[edit] CO2 + H2O + light → CH2O + O2 Calcium Carbonate[edit] Ca2+ + 2HCO3- → CaCO3 + CO2 + H2O. 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. 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] 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] Current sea level rise. Trends in global average absolute sea level, 1870–2008.[1] Changes in sea level since the end of the last glacial episode. Current sea level rise is about 3 mm/year worldwide. According to the US National Oceanic and Atmospheric Administration (NOAA), "this is a significantly larger rate than the sea-level rise averaged over the last several thousand years", and the rate may be increasing.[2] This rise in sea levels around the world potentially affects human populations in coastal and island regions[3] and natural environments like marine ecosystems.[4] Between 1870 and 2004, global average sea levels rose 195 mm (7.7 in), 1.46 mm (0.057 in) per year.[5] From 1950 to 2009, measurements show an average annual rise in sea level of 1.7 ± 0.3 mm per year, with satellite data showing a rise of 3.3 ± 0.4 mm per year from 1993 to 2009,[6] a faster rate of increase than previously estimated.[7] It is unclear whether the increased rate reflects an increase in the underlying long-term trend.[8]
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. While there is some support for this mode in models and in historical observations, controversy exists with regard to its amplitude, and in particular, the attribution of sea surface temperature change to natural or anthropogenic causes, especially in tropical Atlantic areas important for hurricane development.[1] 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. Mechanisms[edit] Climate impacts worldwide[edit] Relation to Atlantic hurricanes[edit]