Feature Publication Archive
Relationship between the spreading rate of ridges and the spatial density (sites/100 km) of active hydrothermal sites on a given ridge segment. Higher spreading rates produce a greater magma supply to drive hydrothermal venting. In the Lau Basin, site production is ~10x higher than on other mid-ocean ridges. Red box in inset: NE Lau Basin.
Baker, E.T., S.L. Walker, G.J. Massoth, and J.A. Resing (2019): The NE Lau Basin: Widespread and abundant hydrothermal venting in the back-arc region behind a superfast subduction zone. Front. Mar. Sci., 6, 382, Pacific Deep-Sea Discoveries: Geological and Biological Exploration, Patterns, and Processes. doi: 10.3389/fmars.2019.00382
Fluids in the Earth’s crust are heated by magma rising to the seafloor where tectonic plates separate or collide. These discharging fluids cool hot rock, construct mineral deposits, nurture biological communities, alter deep-sea mixing and circulation patterns, and profoundly influence ocean chemistry and biology. Since the discovery of deep-sea hydrothermal vents in 1979, scientists have identified more than 700 sites where fluids presently emerge from the seafloor. Over the subsequent 40... more »
Saildrone SD1006 starting its journey from San Francisco, California, to the SPURS-2 region in the eastern tropical Pacific.
Zhang, D., M. Cronin, C. Meinig, T. Farrar, R. Jenkins, D. Peacock, J. Keene, and A. Sutton (2019): Air-sea flux measurements from a new unmanned surface vehicle compared to proven platforms during SPURS-2 field campaign. Oceanography, 32(2), 122–133, doi: 10.5670/oceanog.2019.220.
With the ability to transit thousands of kilometers while making surface observations similar to a moored buoy, the unmanned surface vehicle (USV) Saildrone, manufactured and piloted by Saildrone, Inc., could contribute in important ways to the Global Ocean Observing System (GOOS). Saildrones are powered by renewable energy, using wind for propulsion and solar energy for vehicle control, sensor operation, on-board data processing, and real-time data telemetry. Through a Cooperative Research and Development Agreement (CRADA) between PMEL and Saildrone, sensors for measuring 22 Essential... more »
The 25-year trend in wind speed squared over the tropical Pacific calculated from a popular wind analysis product (Cross-Calibrated Multi-Platform Wind Analysis Version 2, period 1992-2016).
Chiodi, A. M., J. P. Dunne, and D. E. Harrison ( 2019). Estimating air‐sea carbon flux uncertainty over the tropical Pacific: Importance of winds and wind analysis uncertainty. Global Biogeochemical Cycles, 33, 370– 390. doi: 10.1029/2018GB006047
About half of carbon emissions are currently absorbed by natural processes taking place on land and in the ocean. But not all regions of the Earth’s surface act as a sink for emitted CO2. The tropical Pacific Ocean stands out as a significant source of carbon to the atmosphere—even rivaling U.S. emissions. Understanding how this source has changed over recent decades, and how it might change in coming decades is important to understanding and predicting net carbon uptake by the oceans.
Changes in wind speeds over the tropical Pacific Ocean surface are one way in which the... more »
This diagram shows that Pacific cod were caught deeper in warm years (red dots), and shallower in cold years (blue dots), than in near-average years (black dots, average temperature ±1 standard deviation). This is a plot of the deviations in the depth about the mean depth where Pacific cod were caught versus the bottom temperature anomaly (the difference between the temperature in a single year and the multi-year average temperature). The larger the dot, the longer the fish (see scale at top right).
Yang, Q., E. D. Cokelet, P. J. Stabeno, L. Li, A. B. Hollowed, W. A. Palsson, N. A. Bond, and S. J. Barbeaux (2019): How "The Blob" affected groundfish distributions in the Gulf of Alaska. Fish. Oceanogr. https://doi.org/10.1111/fog.12422
In 2014-2016, a marine heat wave, also known as the Blob, produced abnormally warm waters off the US West Coast and in the Gulf of Alaska. Temperatures in the upper 100 meters of the ocean were more than 2.5° C higher than the long term (1981–2010) average from satellite, buoy and ship observations. Many important commercial fish species are groundfish that may not be affected by warm water near the surface. Oceanographers and fisheries scientists from the University of Washington’s Joint Institute for the Study of the Atmosphere and Ocean and NOAA’s Pacific Marine Environmental Laboratory... more »
Estimates of hydrothermal heat flux (MW) for the 33-year time series (black dots; note break on the vertical axis). Pink band at bottom shows "normal" heat flux averaging ~15 MW. Yellow bands show intervals of increased heat flux following eruptions (red triangles and dashed lines), which reached values as high as 1200 MW. About two-thirds of the total heat flux occurred during the 10 years shown by the yellow bands.
Baker, E.T., S.L. Walker, W.W. Chadwick, Jr., D.A. Butterfield, N.J. Buck, and J.A. Resing (2019): Post-eruption enhancement of hydrothermal activity: A 33-year, multi-eruption time series at Axial Seamount (Juan de Fuca Ridge). Geochem. Geophys. Geosyst., 20(2), 814−828, https://doi.org/10.1029/2018GC007802.
About 80% of volcanic activity on Earth occurs on the deep seafloor of the global ocean. These eruptions are concentrated where the Earth’s tectonic plates collide or separate, accelerating the transfer of heat, chemicals, and microbes from the crust to the ocean through hydrothermal venting (the discharge of high-temperature fluids heated within the Earth’s crust) from the seafloor. A primary obstacle to the advancement of our knowledge of submarine eruptions is that most are undetected by conventional monitoring methods.
In 2015, the National Science Foundation’s Ocean... more »