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Southward Migration of the Intertropical Convergence Zone Through the Holocene
The Cariaco Basin record exhibits strong correlations with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global teleconnections among regional climates.
Glacial/interglacial variations in atmospheric carbon dioxide
A version of the hypothesis that the whole-ocean reservoir of algal nutrients was larger during glacial times, strengthening the biological pump at low latitudes, where these nutrients are currently limiting is presented.
Spatial coupling of nitrogen inputs and losses in the ocean
It is concluded that oceanic nitrogen fixation is closely tied to the generation of nitrogen-deficient waters in denitrification zones, supporting the view that nitrogen fixation stabilizes the oceanic inventory of fixed nitrogen over time.
A bacterial method for the nitrogen isotopic analysis of nitrate in seawater and freshwater.
The precision of the method is better than 0.2/1000 (1 SD) at concentrations of nitrate down to 1 microM, and the nitrogen isotopic differences among various standards and samples are accurately reproduced.
Measurement of the oxygen isotopic composition of nitrate in seawater and freshwater using the denitrifier method.
A novel method for measurement of the oxygen isotopic composition (18O/16O) of nitrate (NO3-) from both seawater and freshwater with higher sensitivity, lack of interference by other solutes, and ease of sample preparation is reported.
Influence of the intertropical convergence zone on the East Asian monsoon
High-resolution records of the magnetic properties and the titanium content of the sediments of Lake Huguang Maar in coastal southeast China over the past 16,000 years are presented, using as proxies for the strength of the winter monsoon winds, to suggest that these migrations in the tropical rain belt could have contributed to the declines of both the Tang dynasty in China and the Classic Maya in Central America.
The polar ocean and glacial cycles in atmospheric CO2 concentration
Growing evidence suggests that the Southern Ocean CO2 ‘leak’ was stemmed during ice ages, increasing oceanCO2 storage and making the global ocean more alkaline, driving additional ocean CO2 uptake.
Nitrogen and oxygen isotope fractionation during dissimilatory nitrate reduction by denitrifying bacteria
We report the first measurements of coupled nitrogen (N) and oxygen (O) isotope fractionation of nitrate by laboratory cultures of denitrifying bacteria. Two seawater strains (Pseudomonas stutzeri,
Onset of permanent stratification in the subarctic Pacific Ocean
The surface waters of the modern subarctic Pacific Ocean are isolated from the nutrient-rich waters below by a steep vertical gradient in salinity (halocline), a feature which is a dominant control
Isotopic evidence for source changes of nitrate in rain at Bermuda
[1] Rainwater collected on the island of Bermuda between January 2000 and January 2001 shows pronounced seasonal variation in the nitrogen and oxygen isotopic composition of nitrate. Higher 15N/14N