In the western North Pacific subtropical ocean, the Anatahan volcano of the Mariana Islands erupted on 10 May 2003 for the first time in recorded history. Based on nine different types of remote sensing data provided by NASA, laboratory experiment of the Anatahan samples, and a 3‐D ocean circulation model developed by the U.S. Naval Research Laboratory, the postvolcanic ocean biogeochemical response to the Anatahan eruption was explored. It was observed that soon after the eruption, the aerosol optical depth abruptly increased from the pre‐eruption loading of ∼0.1 to ∼2. In the week following the eruption, a “bloom‐like” patch was observed by NASA's Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) ocean color sensor. Based on the chlorophyll a, fluorescence line height (FLH), at‐sensor total radiance, and normalized water‐leaving radiance data obtained by MODIS, the cause of the bloom‐like patch was diagnosed. The results suggest that the patch was most likely a mixture of suspended volcanic particles and a phytoplankton bloom. FLH was found to be ∼9–17 × 10−3 mW cm−2μm−1 sr−1 in the patch and ∼3–5 × 10−3 mW cm−2μm−1 sr−1 in the ambient water, indicating that a 2–5‐fold increase in biological activity occurred during the week following the eruption. Satellite altimetry indicated that the bloom took place in the presence of downwelling and was not a result of upwelled nutrients in this oligotrophic ocean. Analysis of satellite ocean color spectra of the bloom region found similar spectra as the reference Trichodesmium spectra. Laboratory experiments further substantiate the satellite observations which show elevated concentrations of limiting nutrients provided by the Anatahan samples, and the averaged soluble nitrate, phosphate, and Fe were 42, 3.1, and 2.0 nM, respectively. Though it was not possible to obtain in situ observations of the ocean biogeochemical responses that followed the Anatahan eruption, this study provided evidence based on remote sensing data and laboratory experiment that fertilization of volcanic aerosols occurred following this eruption in one of the most oligotrophic low‐nutrient low‐chlorophyll ocean deserts on Earth.

A statistical evaluation of nearly 10 years of high-resolution surface seawater carbon dioxide partial pressure (pCO 2 ) time-series data collected from coastal moorings around O'ahu, Hawai'i suggest that these coral reef ecosystems were largely a net source of CO 2 to the atmosphere between 2008 and 2016. The largest air-sea flux (1.24 ± 0.33 mol m −2 yr −1 ) and the largest variability in seawater pCO 2 (950 µatm overall range or 8x the open ocean range) were observed at the CRIMP-2 site, near a shallow barrier coral reef system in Kaneohe Bay O'ahu. Two south shore sites, Kilo Nalu and Ala Wai, also exhibited about twice the surface water pCO 2 variability of the open ocean, but had net fluxes that were much closer to the open ocean than the strongly calcifying system at CRIMP-2. All mooring sites showed the opposite seasonal cycle from the atmosphere, with the highest values in the summer and lower values in the winter. Average coastal diurnal variabilities ranged from a high of 192 µatm/day to a low of 32 µatm/day at the CRIMP-2 and Kilo Nalu sites, respectively, which is one to two orders of magnitude greater than observed at the open ocean site. Here we examine the modes and drivers of variability at the different coastal sites. Although daily to seasonal variations in pCO 2 and air-sea CO 2 fluxes are strongly affected by localized processes, basin-scale climate oscillations also affect the variability on interannual time scales.

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Electrodeposited environmental and energy-saving electrodeposited copper alloys materials without silver element will be one of the hotspots on the exploitation of the copper matrix electrical contact field. Theoretically expression of Cu, W, Co and Cu-W-Co alloys electrodeposition possibility is thermodynamically analyzed by the potential-pH plots of Cu-H2O,Co-H2O and W-H2O at normal temperature. It is found that Cu, Co can be deposited together in Cu2+,Co2+aqueous solution. Cu-W isn’t deposited from it’s Cu2+,WO42-aqueous solution, only if Co-W induced deposition under the cobalt ions’ circumstances. So, It is possible that Cu-W-Co alloys are prepared from Cu2+,Co2+,WO42-aqueous solution by the electrodeposition in the theory and experiment, which will be new method and theory for Cu-W-Co serial contact materials’ preparation.