Cyclones Over the Pacific Ocean and Far-Eastern Seas in Cold and Warm Seasons and Their Influence on Wind and Thermal Regime in the Last Two Decade Period

Abstract

Cyclonic activity in the Asia-Pacific region is largely determined by state of the seasonal centers of atmosphere action. In turn, cyclones themselves influence on conditions in certain «key» areas. Recently the Aleutian Low activity declines in fall-winter and this center is shifted westward, but activity of the Hawaiian High increases in warm season. As the result, heightened air pressure prevails over the Ocean (positive anomalies of the sea level pressure) and lowered pressure (negative anomalies) — over the Far Eastern Seas. In this anomalous situation, the number of cyclones over the Ocean has increased but they become weaker that causes SST increasing in the North Pacific both in winter and summer. Over the Bering Sea, the cyclones become weaker, as well, but this regime causes the ice cover increasing, so SST decreasing in spring. On the contrary, over the Okhotsk Sea and Kuril Islands area, the number of cyclones has decreased gradually but they become stronger in both seasons that causes the ice cover reducing and spring SST rising. In the Japan Sea, cyclonic activity has intensified, too, but this tendency causes cooling in winter and warming in summer.

Climatic Changes of Thermal Conditions in the Pacific Subarctic at the Modern Stage of Global Warming

“…2, d), which is also associated with the peculiarity of interannual changes in the atmospheric pressure field in the tropical and extratropical zones of the Pacific Ocean, the state of regional AAC and El Niño [12,37]. According to our estimates and the data published, in winter the time intervals under consideration corresponded to the periods of the greatest exacerbation of the pressure gradient between the Aleutian depression and the Siberian High, in summer -to the warm (positive) phase of the PDO index [17,28,38]. According to the data of coastal meteorological stations, the features of the dynamics of the interannual variation of air temperature anomalies in the eastern and western sectors differ significantly, and the alternation phases of warmer and colder years are well coordinated only within each of these sectors (Fig.…”

“…In the southwest, the study area is bordered by the energy-active zone of the ocean and atmosphere (EAZO) Kuroshio -Oyashio, which is a powerful accumulator and a source of heat to the adjacent areas [16,19,41]. The main routes of typhoon movement pass through this region, and cyclonic activity in the northwestern Pacific Ocean affects the thermal regime characteristics, atmospheric and oceanic circulation of the entire subarctic zone [15,[17][18][19]. According to https://www.esrl.noaa.gov/psd/, in 20-40° N, 125-150° E region from the end of the 1970s there were stable positive trends of an increase in the average annual LЕ and SH fluxes into the atmosphere by about 4-6 W/m -2 for 10 years and 2-3 W/m -2 for 10 years, respectively, and an increase in the speed of southern winds during the summer monsoon by 0.8 m/s, accompanied by a decrease in the heat content of the upper 700-meter layer [6,13].…”

“…In the northern Pacific Ocean, a shift in the climatic regime of the late 1970s is well expressed in the characteristics of interannual oscillations of large-scale anomalies of meteorological and oceanographic parameters, the state of the atmosphere action centers (AAC), as well as indicators of heat and energy exchange between the ocean and the atmosphere [3,4,8,[11][12][13][14]. An important role in the formation of such anomalies belongs to the energy-active zone of the ocean and atmosphere (EAZO) of the northwestern Pacific Ocean and the continuation region of the Kuroshio, associated with increased heat and moisture fluxes from the ocean surface in the torrid zone and temperate latitudes and contributes to the strengthening of tropical and extratropical cyclones, advection of heat to high latitudes and its redistribution between various regions [15][16][17][18][19][20].…”

Climatic Changes of Thermal Conditions in the Pacific Subarctic at the Modern Stage of Global Warming

“…2, d), что также связано с особенностью межгодовых изменений поля атмосферного давления в тропической и внетропической зонах Тихого океана, состояния региональных ЦДА и Эль-Ниньо [12,37]. Согласно нашим оценкам и опубликованным данным, зимой рассматриваемые временные интервалы соответствовали периодам наибольшего обострения барического градиента между алеутской депрессией и сибирским максимумом, летом -теплой (положительной) фазе индекса PDO [17,28,38]. Р и с.…”

“…хорошо выражен в характеристиках межгодовых колебаний крупномасштабных аномалий метеорологических и океанографических параметров, состояния центров действия атмосферы (ЦДА), а также показателей тепло-и энергообмена океана с атмосферой [3,4,8,[11][12][13][14]. Важная роль в процессах формирования таких аномалий принадлежит энергоактивной зоне океана и атмосферы (ЭАЗО) северо-западной части Тихого океана и области продолжения Куросио, что связано с увеличением потоков тепла и влаги с поверхности океана в тропическом поясе и умеренных широтах и способствует усилению тропических и внетропических циклонов, адвекции тепла в высокие широты и его перераспределению между различными районами [15][16][17][18][19][20].…”