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The reappearance of a northeast Pacific marine heatwave (MHW) sounded alarms in late summer 2019 for a warming event on par with the 2013–2016 MHW known as The Blob. Despite these two events having...

Characteristics of eddies in the Gulf of Alaska are assessed from January 2003 through April 2012. Ensemble statistics for eddy subsurface water properties on isopycnals are computed using temperature and salinity profiles from Argo profiling floats located within eddies, which are identified in sea-surface height using objective techniques. Ninety cyclonic and 154 anticyclonic eddies are identified during this period. The anticyclonic eddies are strongly nonlinear and exhibit significant warm subsurface temperature anomalies and associated salty anomalies on isopycnals while no clear distinguishing subsurface anomalies on isopycnals are detected in association with the cyclonic eddies. Heat and freshwater fluxes for the eddies are estimated from integrations in depth coordinates. The anticyclonic eddies transport heat both westward off the continental shelf into the Subarctic Gyre and westward within the Alaskan Stream. However, they transport salt into the Subarctic Gyre and freshwater within the Alaskan Stream. In both pathways eddy heat and freshwater transport show possible year-to-year fluctuations, varying from 0 to 50.4 × 1018 J a−1 and −16.8 to +7.4 km3 a−1, respectively. The anticyclonic eddies are capped by relatively fresh water year-round.

Temperature and salinity both contribute to ocean density, including its seasonal cycle and spatial patterns in the mixed layer. Temperature and salinity profiles from the Argo Program allow construction and analysis of a global, monthly, mixed layer climatology. Temperature changes dominate the seasonal cycle of mixed layer density in most regions, but salinity changes are dominant in the tropical warm pools, Arctic, and Antarctic. Under the Intertropical Convergence Zone, temperature and salinity work in concert to increase seasonal stratification, but the seasonal density changes there are weak because the temperature and salinity changes are small. In the eastern subtropics, seasonal salinity changes partly compensate those in temperature and reduce seasonal mixed layer density changes. Besides a hemispheric seasonal reversal, the times of maximum and minimum mixed layer density exhibit regional variations. For instance, the equatorial region is more closely aligned with Southern Hemisphere timing, and much of the North Indian Ocean has a minimum density in May and June. Outside of the tropics, the maximum mixed layer density occurs later in the winter toward the poles, and the minimum earlier in the summer. Finally, at the times of maximum mixed layer density, some of the ocean has horizontal temperature and salinity gradients that work against each other to reduce the horizontal density gradient. However, on the equatorial sides of the subtropical salinity maxima, temperature and salinity gradients reinforce each other, increasing the density gradients there. Density gradients are generally stronger where either salinity or temperature gradients are dominant influences.

[1] The time-history of sea surface height (SSH) anomaly data from the TOPEX and Jason-1 altimeters is examined along the equator and northward following the west coast of the Americas. Along-track TOPEX and Jason-1 altimeter data are put into an alongshore–offshore coordinate system and then smoothed. This procedure increases the degrees of freedom in individual estimates of long-wavelength coastally trapped waves (CTWs) during times when both satellites are available (2002–2005). Equatorially trapped Kelvin waves are detected during the 2002–2003 El Nino. These Kelvin waves excite CTWs that travel northward along the west coast of the Americas. While CTWs associated with the 2002–2003 equatorial Kelvin waves are not always discernible along the entire coast, correlations of the coastal and equatorial SSH over the entire period of TOPEX and Jason-1 overlap show a clear phase progression. This phase progression implies remote influence of equatorial Kelvin waves that may reach as far north as the Bering Sea during the weak to moderate El Nino events that occurred from 2002 to 2005.

The recent cooling signal in the upper ocean reported by Lyman et al. [2006] is shown to be an artifact that was caused by a large cold bias discovered in a small fraction of Argo floats as well as a smaller but more prevalent warm bias in eXpendable BathyThermograph (XBT) data. These biases are both substantially larger than sampling errors estimated in Lyman et al. [2006].

We observe a net loss of 3.2 (± 1.1) × 10 22 J of heat from the upper ocean between 2003 and 2005. Using a broad array of in situ ocean measurements, we present annual estimates of global upper-ocean heat content anomaly from 1993 through 2005. Including the recent downturn, the average warming rate for the entire 13-year period is 0.33 ± 0.23 W/m 2 (of the Earth's total surface area). A new estimate of sampling error in the heat content record suggests that both the recent and previous global cooling events are significant and unlikely to be artifacts of inadequate ocean sampling.

At the second meeting of the Intergovernmental Oceanographic Commission, held at Paris, France, from September 20 to 29, 1962, the following resolution, introduced by the Japanese delegation, was adopted unanimously. A similar resolution was adopted by the Ninth Annual Eastern Pacific Oceanic Conference, held at Lake Wilderness, Washington, from October 3 to 5, 1962.