Temporal and Spatial Variations in Atmospheric and Oceanic CO₂ in the Western North Pacific from 1990 to 1993

Abstract

The results of atmospheric and oceanic CO2 observations conducted by the Japan Meteorological Agency in the western North Pacific are presented for the period 1990-1993, covering an El Nino/Southern Oscillation (ENSO) event (onset: spring, 1991; withdrawal: summer, 1992). The atmospheric CO2 concentration over the region south of 300N increased drastically between 1990 and 1991 during the winter (4.0ppmv) and summer (4.5ppmv), although the values are not seasonally adjusted. Over the other two years of observations, the growth rates were smaller or at times negative. Oceanic CO2, which is expressed in units of the mole fraction (ppmv) in dry air equilibrated with seawater, showed a significant increase, especially in low latitudes during both seasons of the years 1991-1993, compared to the 1990 values.Oceanic CO2, normalized at a constant temperature, also revealed a significant increase, with larger and smaller magnitudes for winter and summer, respectively. This implies that the increased summer oceanic CO2 results mostly from changes in surface seawater temperature, while for that in winter, other factors, unknown at present, are more related to the increased oceanic CO2.Calculated values of opCO2 and CO2 flux at the air-sea interface reveal that in winter, the region north of 100N acts as a sink of CO2, with a maximum net flux of --10.0mmolm-2d-1.The region south of 100N, however, at times becomes a weak source of CO2, with a maximum net flux of 2.4mmolm-2d-1. In summer, the western North Pacific becomes a weak source or is almost in equilibrium with atmospheric CO2.The increase in winter oceanic CO2 or 4pCO2, as related to the 1991/92 ENSO event, is not as distinct as in the 1982/83 ENSO event, although lower temperatures and higher salinity in the surface seawater were commonly found during both the events.The response of the CO2 flux in the tropical western North Pacific to the 1991/92 ENSO event was rather small compared to the magnitude of the rate changes obtained in previous results for the central or eastern tropical Pacific.

Static Water Structure Detected by Heat Capacity Measurements on Aqueous Solutions of a Triple-Helical Polysaccharide Schizophyllan

“…17,35 So far the order-disorder transition for schizophyllan has been experimentally studied by optical rotation, heat capacity, dielectric dispersion, and cholesteric pitch. 12,13,[28][29][30][31][32][33][36][37][38][39] It is also noted that the transition is highly cooperative from remarkable dependence on the polymer molecular weight. 13,29,30 It has been shown 13,29,30,40 that the molecular mechanism for this transition obeys the linear cooperative system of Zimm and Bragg 41 and Nagai.…”

“…13,29,30 It has been shown 13,29,30,40 that the molecular mechanism for this transition obeys the linear cooperative system of Zimm and Bragg 41 and Nagai. 42,43 From dielectric studies, 12,36,37 water in aqueous schizophyllan solutions exists in different structures, which are classified into four different types, i.e., bound water, structured water, loosely structured water, and free water from the surface of the helix core to outward, which are in the increasing order of mobility. However, heat capacity and dielectric dispersion data so far obtained were not detailed enough to analyze such structures in quantitative terms.…”

Sc3p Hydrophobin Organization in Aqueous Media and Assembly onto Surfaces As Mediated by the Associated Polysaccharide Schizophyllan

“…Schizophyllan has also been reported to exist as a triple helix in aqueous solution. [41][42][43][44][45] In previous literature studies, the role of the co-secreted schizophyllan in protein stabilization and subsequent film formation was not recognized. Recently, we examined the constituents of clarified culture supernatant from the fungus Schizophyllum commune and the respective roles of each in coating hydrophobic and hydrophilic surfaces.…”

Trend analysis of O3 and CO in the period 1980–1996: A three‐dimensional model study

“…This effect is enhanced through the positive CO-OH feedback mechanism at low NOx concentraions. A part of the discrepancy between the modeled and observed trends can probably be explained by changes in the transport pattern, for example, due to the ENSO events[Murata and Fushimi, 1996]. This effect is not captured by the model calculations as the same 1-year meteorological archive that is used for each of the 17 years of the study.At Mahe and Ascension Islands, the calculations give positive trends for both seasons as a consequence of the estimated increasing emission rate over Africa (seeFigure 1).…”