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 major biopolymeric component to dissolved organic carbon in surface sea water

Abstract: Organic carbon dissolved in sea water is an important component of the global carbon cycle1. Concentrations of dissolved organic carbon (DOC) in the ocean's surface mixed layer are at least twice those in the deep sea2,3, because of the production of soluble carbon compounds by marine algae in the euphotic zone4,5. But very little is known about the chemical composition of DOC, and the connection between photosynthetic production and DOC accumulation is not well understood6,7. Here we report the chemical characterization of macromolecular DOC at several sites in the Atlantic and Pacific oceans. Neutral sugars, acetate and lipids show similar distributions, suggesting that these constituents are linked together in a common macromolecular structure. Chemical linkage patterns between the oligosaccharide portions of dissolved organic matter subjected to ultrafiltration are highly specific, with little variation between ocean basins. We show that laboratory culture experiments on the decomposition of algal exudate produce macromolecular organic matter with similar compositions and linkage characteristics. We propose that a significant fraction of DOC in sea surface water consists of structurally related and biosynthetically derived acyl oligosaccharides that persist after more labile organic matter has been degraded.

The economic effects of harmful algal blooms in the United States: Estimates, assessment issues, and information needs

Abstract: During the last several decades, harmful algal bloom (HAB) events have been observed in more locations than ever before throughout the United States. Scientists have identified a larger number of algal species involved in HABs, more toxins have been uncovered, and more fisheries resources have been affected. Whether this apparent increase in HAB events is a real phenomenon or is the result of increased sampling and monitoring is a topic of intense discussions within the scientific community. We also have an inchoate understanding of the reasons for the apparent increase, particularly concerning the role of anthropogenic nutrient loadings as a causal factor. Whatever the reasons, virtually all coastal regions of the U.S. are now regarded as potentially subject to a wide variety and increased frequency of HABs. It is important to begin to understand the scale of the economic costs to society of such natural hazards. It is a common, but not yet widespread, practice for resource managers and scientists in many localities to develop rough estimates of the economic effects of HAB events in terms of lost sales in the relevant product or factor markets, expenditures for medical treatments, environmental monitoring and management budgets, or other types of costs. These estimates may be invoked in policy debates, often without concern about how they were developed. Although such estimates are not necessarily good measures of the true costs of HABs to society, they may help to measure the scale of losses and be suggestive of their distribution across political jurisdictions or industry sectors. With adequate interpreta- tion, our thinking about appropriate policy responses may be guided by these estimates. Here we compile disparate estimates of the economic effects of HABs for events in the U.S. where such effects were measured during 1987-1992. We consider effects of four basic types: public health, commercial fisheries, recreation and tourism, and monitoring and management. We discuss many of the issues surrounding the nature of these estimates, their relevance as measures of the social costs of natural hazards, and their potential for comparability and aggregation into a national estimate.

Warm tropical ocean surface and global anoxia during the mid-Cretaceous period

Abstract: The middle of the Cretaceous period (about 120 to 80 Myr ago) was a time of unusually warm polar temperatures, repeated reef-drowning in the tropics and a series of oceanic anoxic events (OAEs) that promoted both the widespread deposition of organic-carbon-rich marine sediments and high biological turnover. The cause of the warm temperatures is unproven but widely attributed to high levels of atmospheric greenhouse gases such as carbon dioxide. In contrast, there is no consensus on the climatic causes and effects of the OAEs, with both high biological productivity and ocean 'stagnation' being invoked as the cause of ocean anoxia. Here we show, using stable isotope records from multiple species of well-preserved foraminifera, that the thermal structure of surface waters in the western tropical Atlantic Ocean underwent pronounced variability about 100 Myr ago, with maximum sea surface temperatures 3-5 degrees C warmer than today. This variability culminated in a collapse of upper-ocean stratification during OAE-1d (the 'Breistroffer' event), a globally significant period of organic-carbon burial that we show to have fundamental, stratigraphically valuable, geochemical similarities to the main OAEs of the Mesozoic era. Our records are consistent with greenhouse forcing being responsible for the warm temperatures, but are inconsistent both with explanations for OAEs based on ocean stagnation, and with the traditional view (reviewed in ref. 12) that past warm periods were more stable than today's climate.