Woods Hole Oceanographic Institution

About: Woods Hole Oceanographic Institution is a nonprofit organization based out in Falmouth, Massachusetts, United States. It is known for research contribution in the topics: Population & Mantle (geology). The organization has 5685 authors who have published 18396 publications receiving 1202050 citations. The organization is also known as: WHOI.

A new high pressure equation of state for seawater

Abstract: A new high pressure equation of state for water and seawater has been derived from the experimental results of Millero and coworkers in Miami and Bradshaw and Schleicher in Woods Hole The form of the equation of state is a second degree secant bulk modulus K = Pv0(v0−vp=K0+AP+BP2 K = Kw0+aS+bS32 A = Aw+cS+dS32 B = Bw+eS where ν0 and νP are the specific volume at 0 and P applied pressure and S is the salinity (ℵ) The coefficients KWO, AW, and BW for the pure water part of the equation are polynomial functions of temperature The standard error of the pure water equation of state is 43 × 10−6 cm3 g−1 in νWP The temperature dependent parameters a, b, c, d, and e have been determined from the high pressure measurements on seawater The overall standard error of the seawater equation of state is 90 × 10−6 cm3 g−1 in νP Over the oceanic ranges of temperature, pressure, and salinity the standard error is 50 × 10−6 cm3 g−1 in νP This new high pressure equation of state has recently (1979) been recommended by the UNESCO Joint Panel on Oceanographic Tables and Standards for use by the oceanographic community

Major impacts of climate change on deep-sea benthic ecosystems

Abstract: The deep sea encompasses the largest ecosystems on Earth. Although poorly known, deep seafloor ecosystems provide services that are vitally important to the entire ocean and biosphere. Rising atmospheric greenhouse gases are bringing about significant changes in the environmental properties of the ocean realm in terms of water column oxygenation, temperature, pH and food supply, with concomitant impacts on deep-sea ecosystems. Projections suggest that abyssal (3000–6000 m) ocean temperatures could increase by 1°C over the next 84 years, while abyssal seafloor habitats under areas of deep-water formation may experience reductions in water column oxygen concentrations by as much as 0.03 mL L –1 by 2100. Bathyal depths (200–3000 m) worldwide will undergo the most significant reductions in pH in all oceans by the year 2100 (0.29 to 0.37 pH units). O 2 concentrations will also decline in the bathyal NE Pacific and Southern Oceans, with losses up to 3.7% or more, especially at intermediate depths. Another important environmental parameter, the flux of particulate organic matter to the seafloor, is likely to decline significantly in most oceans, most notably in the abyssal and bathyal Indian Ocean where it is predicted to decrease by 40–55% by the end of the century. Unfortunately, how these major changes will affect deep-seafloor ecosystems is, in some cases, very poorly understood. In this paper, we provide a detailed overview of the impacts of these changing environmental parameters on deep-seafloor ecosystems that will most likely be seen by 2100 in continental margin, abyssal and polar settings. We also consider how these changes may combine with other anthropogenic stressors (e.g., fishing, mineral mining, oil and gas extraction) to further impact deep-seafloor ecosystems and discuss the possible societal implications.

Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect

Abstract: Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice.

Circulation and larval distribution in internal tidal bore warm fronts

Abstract: Internal tidal bore warm fronts were observed during the summer of 1996 off the coast of Southern California. Warm bore fronts had concentrating currents resulting from high-frequency internal motions and from a larger two-way flow; the two-way flow featured surface currents onshore and bottom currents offshore. A sharp thermocline depression and high-frequency, large-amplitude internal motions followed the leading edge of the bore, with downwelling currents on the trailing side of the crest of the nonlinear internal waves and upwelling currents in front of the crest. Warm bores propagated onshore with a propagation speed, c, that ranged from 10.6 to 19.6 cm s -1 , while time-averaged frontal currents, ū, varied from 11.2 to 17.6 cm s -1 in the shallowest bin. In one out of three cases ū > c, which implied that there were faster currents than the rate of advance of the front and which implied that the origin of surface frontal material is behind the front, not in front of it. Three invertebrate larval taxa were found at all sites across fronts, but only two intertidal barnacles, Pollicipes polymerus and Chthamalus spp., were concentrated at the front's surface, while the subtidal bryozoan Membranipora spp. was not. Frontal Pollicipes were more concentrated than were Chthamalus. The frontal downwelling currents observed suggested that concentrated larvae would have to swim upward in order to maintain depth. Pollicipes were abundant on the offshore warm side of the fronts but were absent or rare on the onshore colder side, suggesting that the origin of frontal Pollicipes was behind the front, although an alternative cannot be ruled out conclusively. Chthamalus were more abundant at depth than at the surface at all sites except at the front, where this pattern was reversed. The origin of frontal Chthamalus is uncertain. Membranipora were more abundant on the onshore colder side of the fronts, and abundances were usually higher at depth than at surface. Lack of accumulation in this species may be due to its limited swimming capability.

Enhanced CO2 outgassing in the Southern Ocean from a positive phase of the Southern Annular Mode

Abstract: [1] We investigate the interannual variability in the flux of CO2 between the atmosphere and the Southern Ocean on the basis of hindcast simulations with a coupled physical-biogeochemical-ecological model with particular emphasis on the role of the Southern Annular Mode (SAM). The simulations are run under either pre-industrial or historical CO2 concentrations, permitting us to separately investigate natural, anthropogenic, and contemporary CO2 flux variability. We find large interannual variability (±0.19 PgC yr−1) in the contemporary air-sea CO2 flux from the Southern Ocean (<35°S). Forty-three percent of the contemporary air-sea CO2 flux variance is coherent with SAM, mostly driven by variations in the flux of natural CO2, for which SAM explains 48%. Positive phases of the SAM are associated with anomalous outgassing of natural CO2 at a rate of 0.1 PgC yr−1 per standard deviation of the SAM. In contrast, we find an anomalous uptake of anthropogenic CO2 at a rate of 0.01 PgC yr−1 during positive phases of the SAM. This uptake of anthropogenic CO2 only slightly mitigates the outgassing of natural CO2, so that a positive SAM is associated with anomalous outgassing in contemporaneous times. The primary cause of the natural CO2 outgassing is anomalously high oceanic partial pressures of CO2 caused by elevated dissolved inorganic carbon (DIC) concentrations. These anomalies in DIC are primarily a result of the circulation changes associated with the southward shift and strengthening of the zonal winds during positive phases of the SAM. The secular, positive trend in the SAM has led to a reduction in the rate of increase of the uptake of CO2 by the Southern Ocean over the past 50 years.