[1] A worldwide compilation of atmospheric total phosphorus (TP) and phosphate (PO 4 ) concentration and deposition flux observations are combined with transport model simulations to derive the global distribution of concentrations and deposition fluxes of TP and PO 4 . Our results suggest that mineral aerosols are the dominant source of TP on a global scale (82%), with primary biogenic particles (12%) and combustion sources (5%) important in nondusty regions. Globally averaged anthropogenic inputs are estimated to be $5 and 15% for TP and PO 4 , respectively, and may contribute as much as 50% to the deposition over the oligotrophic ocean where productivity may be phosphorus-limited. There is a net loss of TP from many (but not all) land ecosystems and a net gain of TP by the oceans (560 Gg P a À1

[1] We report a CO 2 emission rate of 8500 metric tons per day (t d À1 ) for the summit of K lauea Volcano, several times larger than previous estimates. It is based on three sets of measurements over 4 years of synchronous SO 2 emission rates and volcanic CO 2 /SO 2 concentration ratios for the summit correlation spectrometer (COSPEC) traverse. Volcanic CO 2 /SO 2 for the traverse is representative of the global ratio for summit emissions. The summit CO 2 emission rate is nearly constant, despite large temporal variations in summit CO 2 /SO 2 and SO 2 emission rates. Summit CO 2 emissions comprise most of K lauea's total CO 2 output ($9000 t d À1 ). The bulk CO 2 content of primary magma determined from CO 2 emission and magma supply rate data is $0.70 wt %. Most of the CO 2 is present as exsolved vapor at summit reservoir depths, making the primary magma strongly buoyant. Turbulent mixing with resident reservoir magma, however, prevents frequent eruptions of buoyant primary magma in the summit region. CO 2 emissions confirm that the magma supply enters the edifice through the summit reservoir. A persistent several hundred parts per million CO 2 anomaly arises from the entry of magma into the summit reservoir beneath a square kilometer area east of Halemaumau pit crater. Since most of the CO 2 in primary magma is degassed in the summit, the summit CO 2 emission rate is an effective proxy for the magma supply rate. Both scrubbing of SO 2 and solubility controls on CO 2 and S in basaltic melt cause high CO 2 /SO 2 in summit emissions and spatially uncorrelated distributions of CO 2 and SO 2 in the summit plume.

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