an antarctic ice core reveals atmospheric co2 variations over the past few centuries
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OLR (1985) 32 (12) B. Marine Meteorology 1001
monitoring monsoon circulation and year-to-year variability. Here, monthly mean OLR data are analyzed for dominant eigenvector patterns, with the first three explaining nearly 93% of the total variance, being associated respectively with a sea- sonal shift in the cloudiest area of the ITCZ, a phase lag relationship between north India and the tropics, and the major features of the northeast monsoon over southeastern India. Interannual OLR variation shows close relationships to total monsoon rainfall over India. Indian Inst. of Tropical Meteorol., Pune 411005, India. (fcs)
BI10. Climate, climatology
85:6964 Raynaud, D. and J.M. Barnola, 1985. An Antarctic
ice core reveals atmospheric CO 2 variations over the past few centuries. Nature, Lond., 315(6017): 309-31 I.
By analysing the air extracted from bubbles found in the ice, it is possible to determine the air compo- sition, and thus its CO 2 content, for the period during which the air was trapped. Results obtained from an Antarctic ice core indicate that the back:- ground level could have been as low as 260 ppmv before the major anthropogenic influence and suggest that the so-called 'pre-industrial' CO 2 level was not constant over the few hundred years preceding the nineteenth century. Lab. de Glac. et Geophys. de l'Environ., BP 96, 38402 St. Martin d'Heres Cedex, France.
85:6965 Wigley, T.M.L. and M.E. Schlesinger, 1985. Ana-
lytical solution for the effect of increasing CO2 on global mean temperature. Nature, Lond., 315(6021):649-652. Climatic Res. Unit, Univ. of East Anglia, Norwich NR4 7T J, UK.
BI40. Air-sea interactions
85:6966 Adamec, David and R.L. Elsberry, 1985. Response
of an intense oceanic current system to cross- stream cooling events. J. phys. Oceanogr., 15(3): 273-287.
Shifts in location and strength of an intense oceanic flow such as the Gulf Stream in response to cross-stream gradient cooling are studied using 2-D simulations. The response is highly dependent on the vertical exchanges of both heat and momentum.
Several case studies in which these exchanges are varied are discussed. Further simulations in which surface wind stress varies are also presented and compared with cases of only thermal forcing. Dept. of Meteorol., Naval Postgrad. Sch., Monterey, CA 93943, USA. (who)
85:6967 Anderson, D.L.T. and J.P. McCreary, 1985. Slowly
propagating disturbances in a coupled ocean- atmosphere model. J. atmos. Sci., 42(6).'615-629.
A previously developed simple, coupled ocean- atmosphere model of E1 Nifio and the Southern Oscillation is extended to include a reduced gravity ocean model wih explicit thermodynamics with both horizontal advection and vertical redistribution of heat. The atmosphere is modeled as a linear, single baroclinic mode driven by surface latent heat convection which is specified in terms of the ocean temperature. Land, with prescribed surface convec- tion, is also included. Three cases of land-ocean configuration, no land and a bounded ocean with strong convection either east or west of the ocean, are studied and compared with observations. Dept. of Atmos. Phys., Clarendon Lab., Oxford OX1 3PU, UK. (wbo)
85:6968 Birman, B.A. and E.V. Balashova, 1985. On the
problem of calculating the fields of tangential stress of wind near the ocean surface. Meteor- ologiya Gidrol., 3:75-82. (In Russian, English abstract.)
Results of calculating the modulus of the mean vector of tangential wind stress from the mean wind speed and its variability are close to those derived using standard time data when the tangential stress is calculated for each wind velocity measurement and then averaged. Fields of tangential wind stress near the surface of the North Atlantic are compared with data of Hellerman and Bunker. In tropical latitudes, the cross-correlation coefficients of fields are equal to 0.92 for March and 0.96 for August; differences in moderate latitudes are associated with wind velocity trends. Results demonstrate the dom- inant role of tropical latitudes in exchange of momentum between the ocean and atmosphere.
85:6969 Clarke, A.J. and K.H. Brink, 1985. The response of
stratified, frictional flow of shelf and slope waters to fluctuating large-scale, low-frequency wind forcing. J. phys. Oceanogr., 15(4):439-453.
Models are developed to examine large-scale, low- frequency, wind-driven fluctuations over the con- tinental shelf and slope in the presence of density