271 research outputs found
From risk management to ERM
Full text linkAt one point in time, there was self-insurance. Then came risk management. Now comes the era of enterprise risk management(ERM). Traditional risk management will always be necessary, but ERM will complement existing risk activities by extending the field to cover all core risks as well as emerging and strategic opportunities, because without taking risks, organisations gain no value. This paper will present the main elements of an ERM framework and characteristics of different types of ERM.ERM, CRO, risk management, risk designation, risk framework, risk system, risk culture, governance, risk intelligence, risk capital, GIR
Carbon isotope ratios of organic compound fractions in oceanic suspended particles
No full textTo study cycling of organic fractions in the ocean, relative abundances and radio- and stable-carbon isotope measurements of total lipid extract, acid-soluble, and acid-insoluble fractions of suspended particulate organic carbon (POC) were made. Changes in relative abundances occurred mostly in the upper 1000 m of the water column, with a decrease in total lipid extract and the acid-soluble fraction and an increase in the acid-insoluble fraction with increasing depth. We found lower Delta(14)C values for total lipid extract and the acid-insoluble fraction than for the acid-soluble fraction, which is consistent with the previous suggestion of incorporation of dissolved organic carbon and/or resuspended sediment to POC (Druffel and Williams, 1990; Sherrell et al., 1998). The Delta(14)C values of these fractions in a given organic carbon pool must be understood in terms of acquisition of (14)C-depleted carbon from other carbon pools in addition to aging within the reservoir.X1113sciescopu
Incorporation of aged dissolved organic carbon (DOC) by oceanic particulate organic carbon (POC): An experimental approach using natural carbon isotopes
No full textIncorporation of 14 C-depleted (old) dissolved organic carbon (DOC) on/into particulate organic carbon (POC) has been suggested as a possible mechanism to explain the low Delta C-14-POC values observed in the deep ocean [Druffel, E.R.M., Williams, P.M., 1990. Identification of a deep marine source of particulate organic carbon using bomb C-14. Nature, 347, 172-174.]. A shipboard incubation experiment was performed in the Sargasso Sea to test this hypothesis. Finely ground dried plankton was incubated in seawater samples from the deep Sargasso Sea, both with and without a biological poison (HgCl2). Changes ill parameters such as biochemical composition and carbon isotopic signatures of bulk POC and its organic compound classes were examined to study the roles of sorptive processes and biotic activity on POC character. Following a 13-day incubation, the relative abundance of the acid-insoluble organic fraction increased. Abundances of extractable lipids and total hydrolyzable amino acids decreased for both treatments, but by a greater extent in the non-poisoned treatment. The Delta C-14 values of POC recovered from the non-poisoned treatment were significantly lower than the value of the unaltered plankton material used for the incubation, indicating incorporation of C-14-depleted carbon, most likely DOC. The old carbon was present only in the lipid and acid-insoluble fractions. These results are consistent with previous findings of old carbon dominating the same organic fractions of sinking POC from the deep Northeast Pacific [Hwang, J., Druffel, E.R.M., 2003. Lipid-like material as the Source of the uncharacterized organic carbon in the ocean? Science, 299, 881-884.]. However, the Delta C-14 values of POC recovered from the poisoned treatment did not change as much as those from the non-poisoned treatment suggesting that biological processes were involved in the incorporation of DOC on/into POC. (c) 2005 Elsevier B.V. All rights reserved.X1122sciescopu
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Detection of El Nino and decade time scale variations of sea surface temperature from banded coral records: implications for the carbon dioxide cycle.
Full text linkStable oxygen isotope ratios from annually banded corals are correlated with historical records of sea surface temperature in the central and eastern tropical Pacific ocean. El Nino events between 1929 and 1976 are detected using this method, but there are discrepancies between the records of El Ninos from corals and those determined using historical hydrographic and meteorologic data. The average annual description of delta 18O during El Nino events is greater at the Galapagos Island sites (0.45per mille) than at the Fanning and Canton Island sites in the mid-Pacific (0.20-0.30per mille and less than 0.2per mille, respectively). Of prime importance is evidence of decade time scale variability of sea surface temperature (SST) in the tropical Pacific. In particular, annually averaged SST appears to have been 0.5o-1oC higher in the eastern tropical Pacific during the 1930's than during subsequent years. A significant net flux of CO2 from the surface ocean to the atmosphere is envisioned during these periods of higher SST.-Autho
Detection of El Nino and decade time scale variations of sea surface temperature from banded coral records: implications for the carbon dioxide cycle.
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Lipid-like material as the source of the uncharacterized organic carbon in the ocean?
No full textThe composition and formation mechanisms of the uncharacterized fraction of oceanic particulate organic carbon (POC) are not well understood. We isolated biologically important compound classes and the acid-insoluble fraction, a proxy of the uncharacterized fraction, from sinking POC in the deep Northeast Pacific and measured carbon isotope ratios to constrain the source(s) of the uncharacterized fraction. Stable carbon and radiocarbon isotope signatures of the acid-insoluble fraction were similar to those of the lipid fraction, implying that the acid-insoluble fraction might be composed of selectively accumulated lipid-like macromolecules.X1155sciescopu
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