Oceanographic Regions and Assessment of Temperature Structure in the Seasonal Zone of the North Pacific Ocean

1964 ◽  
Vol 21 (5) ◽  
pp. 941-970 ◽  
Author(s):  
John P. Tully

There are eight climatic regions from the Equator to the Arctic in the Pacific Ocean. In each region the distinct oceanographic temperature structures and their seasonal sequences are described and related to surface weather processes and transport. Procedures for observation and interpretation of data must be adapted to suit the regional models of structure and behaviour. However, a rational universal system of information presentation is feasible and is demonstrated. The concepts may be extended to other oceans.

2021 ◽  
Author(s):  
Elena Golubeva ◽  
Gennady Platov ◽  
Marina Kraineva

<p>As a result of the analysis of the NOAA surface temperature observational data (Huang et al., 2020), the periods corresponding to "marine heatwaves" in the northeastern Pacific Ocean (2013-2019) were identified. Marine heatwaves were defined as exceeding the 90th percentile threshold. The same analysis of the temperature in the Bering Strait's immediate vicinity showed anomalously warm waters in the same years. Analysis of the pressure field, which forms the atmosphere's dynamic state and affects the water circulation system of the Bering Sea, allowed us to assume the inflow of anomalously warm Pacific waters into the Chukchi Sea. To analyze the North Pacific heatwaves' consequences for the Arctic Ocean, we carried out two numerical experiments using the regional ocean and sea ice model SibCIOM (Golubeva et al., 2018) and NCEP/NCAR atmospheric reanalysis data (Kalnay et al., 1996). The first numerical experiment was carried out to calculate hydrodynamic and ice fields from January 2000 to November 2020 (Experiment 1). On the Arctic and the Pacific Ocean boundary in the Bering Strait, we used the monthly average climatic values ​​of the transport, temperature, and salinity of waters coming from the Pacific Ocean. Experiment 2 was carried out from 2014 to November 2020. The calculated values ​​of hydrological and ice characteristics obtained in Experiment 1 were used as the initial state for this experiment. In contrast to Experiment 1,  a heat flux exceeding the average climatic values ​​was set at the Bering Strait in Experiment 2. Its assignment was provided by using temperature values ​​from observational data in the Bering Strait vicinity (Huang et al., 2020). Comparison of monthly average hydrological and ice fields obtained in two numerical experiments and analysis of numerical results showed that an increase in the temperature of the Pacific waters entering the Arctic shelf through the Bering Strait leads to an increase in the heat content of the Chukchi Sea waters, heat transfer by currents in the surface and subsurface layers, a gradual increase in the heat content of the Beaufort Sea, and the reduction of Arctic ice cover. The increase in heat content in Experiment 2 for the Beaufort Sea was obtained in both the upper 50-meter and 250-meter layers.</p><p>The research is supported by the Russian Science Foundation, grant №. 19-17-00154.</p>


2020 ◽  
Author(s):  
Zhichun Zhang ◽  
huijie Xue

<p>            Based on a nonlinear reduced gravity model simulation, formation cause of Subtropical Countercurrent(STCC) in the Pacific Ocean are investigated. The model reproduces well the characteristics of circulation of thermocline in the North pacific Ocean. The results suggest that the variation of the west boundary topography, especially the witdh of the luzon strait, play a key role on the formationg of STCC as well as the wind sress meridional gradient. When the witdh of the luzon strait gradually decrease, the STCC increase . the model results also reveal that the wind stress dipole curl of west ot the hawaii islands is key to the HLCC formation.</p>


2020 ◽  
Vol 13 (5) ◽  
pp. 7-30
Author(s):  
A. Y. Petrov ◽  
V. N. Kostornichenko ◽  
M. M. Koskina

The article reviews the initial period of European colonization of the North Pacific Ocean and California within the context of diplomatic relations between Russia and Spain during the late 17th and early 18th centuries. It tries to understand the policies of European powers in the American Northwest and the reasons for pursuing their colonial interests there. It analyses the history of exploration of these territories, expeditions to the northern part of the Pacific Ocean, and historical maps of this region. For the first time in Russian historiography the authors touch upon the exploration of California in the 18th century.The exploration of the North Pacific Ocean, the northwestern American coast, including certain areas of California, Alaska and the Aleutian Islands has long attracted the attention of European powers. It was a process in which government authorities and private merchant companies took part. The expansion of the Spanish Empire into California was made possible in part because of the concerns of the Madrid court about the strengthening of the Russian and British empires in the North Pacific Ocean. The Spanish documents from the archives of Madrid, Seville and Simancas – the article introduces them into research communication the first time - show the validity of the fears of the Madrid court regarding the inevitable development of Russian colonization in the region. The advance of Russia to the shores of America has economic reasons: Cossacks and merchants reached the Pacific Ocean pursuing the desire to profit from the fur trade. As the economic influence expanded, the state interests of annexing territories and bringing the local population into citizenship followed behind. The territorial advance of the Russians to the Pacific Ocean was facilitated by the ambitious, but at the same time balanced diplomacy of Peter I, which managed to ensure the expansion of the borders of the Russian Empire.Spanish consolidation in certain territories in California was aimed at a possible containment of the Russian advance. Russian-Spanish relations in the Northwest Pacific at the end of the 17th – 18th centuries contributed to the nature of the subsequent development of territories in the North Pacific Ocean.


1993 ◽  
Vol 50 (12) ◽  
pp. 2608-2625 ◽  
Author(s):  
William G. Pearcy ◽  
Joseph P. Fisher ◽  
Mary M. Yoklavich

Abundances of Pacific pomfret (Brama japonica), an epipelagic fish of the North Pacific Ocean, were estimated from gillnet catches during the summers of 1978–1989. Two size modes were common: small pomfret <1 yr old, and large fish ages 1–6. Large and small fish moved northward as temperatures increased, but large fish migrated farther north, often into the cool, low-salinity waters of the Central Subarctic Pacific. Lengths of small fish were positively correlated with latitude and negatively correlated with summer surface temperature. Interannual variations in the latitude of catches correlated with surface temperatures. Large catches were made in the eastern Gulf of Alaska (51–55°N) but modes of small pomfret were absent here, and large fish were rare at these latitudes farther to the west. Pomfret grow rapidly during their first two years of life. They are pectoral fin swimmers that swim continuously. They prey largely on gonatid squids in the region of the Subarctic Current in the Gulf of Alaska during summer. No evidence was found for aggregations on a scale ≤1 km. Differences in the incidence of tapeworm, spawning seasons, and size distributions suggest the possibility of discrete populations in the North Pacific Ocean.


2020 ◽  
Author(s):  
Yayoi Inomata ◽  
Michio Aoyama

&lt;p&gt;We investigated spatial and temporal variations in 137Cs concentrations in the surface waters of the global ocean for the period from 1957 to 2018. In order to study the distribution of 137Cs concentrations in surface seawater, we divided the global ocean into 37 latitudinal boxes on the basis of known ocean current systems, latitudinal and longitudinal distributions of 137Cs concentrations, the distribution of global fallout, locations of nuclear reprocessing plants, fallout from the Chernobyl accident, and release from Fukushima Nuclear Power Plant accident. Based on the 0.5-y average value of 137Cs concentrations in the surface water in each box, we classified the temporal variations into four types. In the North Pacific Ocean where there was high fallout from atmospheric nuclear weapons tests, the rates of decrease in the 137Cs concentrations changed over the five decades: the rate of decrease from the 1950s to the 1970s was much faster than that after the 1970s, and the 137Cs concentrations were almost constant after the 1990s. Latitudinal differences in 137Cs concentrations in the North Pacific Ocean became small with time. After March 2011, extremely high concentrations (3.26&amp;#215;107 Bq/m3) were observed in the western North Pacific Ocean based on the direct release and atmospheric deposition of FNPP1-derived 137Cs. In the equatorial Pacific and Indian Oceans, the 137Cs concentrations varied within a constant range in the 1970s and 1980s, due to the advection of 137Cs from areas of high global fallout in the mid-latitudes of the North Pacific Ocean. In the eastern South Pacific and Atlantic Oceans (south of 40&amp;#176;S), the concentrations decreased exponentially over the six decades. In the Arctic and North Atlantic Oceans, including marginal seas, 137Cs concentrations were strongly controlled by discharge from nuclear reprocessing plants after the late 1970s. The 137Cs concentrations were rapidly decreased after the early 1980s, and advected into the Arctic Ocean.&amp;#160;&lt;br&gt;The averaged 137Cs concentrations in each box in the year of 1970 were 1-716 Bq/m3, and those were decreased to 0.2-28 Bq/m3 in the year of 2010. The apparent half-residence times of 137Cs in the surface waters of the global ocean from 1970 to 2010 ranged from 4.2 to 48.1 years for each box.&amp;#160;&lt;/p&gt;&lt;p&gt;(Reference)&lt;br&gt;Inomata et al. (2009) Analysis of 50-y record of surface 137Cs concentrations in the global ocean using the HAM-global database. Journal of Environmental Monitoring, DOI: 10.1039/b811421h.&amp;#160;&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;


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