The Sea of Okhotsk: some conceptions applying to climate-oceanography events and fish resources Sen Tok Kim Sakhalin Scientific Research Institute of Fisheries & Oceanography (SakhNIRO)
Circulation system in the North Pacific, 1 Alaskan Gyre, Western Subarctic Gyre, 3 Bering Subarctic Gyre, 4 Okhotsk Subarctic Gyre. Currents: 5 Alaskan, 6 East Kamchatka, 7 West Kamchatka, 8 Soya, 9 Oyashio, 1 Kuroshio, 11 Subarctic, 1 North Pacific (Ohtani, 1991) 4 7 6 8 9 11 5 1 1
The Sea of Okhotsk cyclonic Gyre in the warm period (July-September) (Chernyavskyi et al., 1993) Oyashio East Kamchatka Currents 1-West Kamchatka -Northern 3-Median 4-Penzhinskoye 5-Yamskoye 6-North Okhotsk 7-North Okhotsk Counter 8-Amur 9-East Sakhalin 1-East Sakhalin Counter 11-North-Eastern 1-Soya Soya 3
ice cover, sea area 1 5 Average ice cover in March 1971-199 (JMA, 1991): 1 - >9 of probability, - 7-9, 3 3-7, 4 1-3, 5 - <1 The Sea of Okhotsk: ice cover (), surface air and bottom water temperature 1 1 196 1965 197 1975 198 1985 199 1995 5 T 15 m, C Febrary March March T15 m Линейная (Febrary March) A ir T e m p e ra tu re ( C ) Ice cover averaged in February-March 196-9 and bottom water temperature averaged for depth 15- m in July 1965-4 (Zhigalov, Luchin, 1; Figurkin, 6) 4 3 1-1 - -3-4 4 3 1 1 3 4 195 196 197 198 199 Air temperature anomaly in October-March over northeastern Eurasia (red) and annual sea ice extent anomaly in the Sea of Okhotsk (February)(blue)(Ohshima et al., 6). 4 Sea ice extent (x1 km)
Water transport of the Western Kamchatka Current (Northern Branch) within the - m layer in April 1983-6 (Figurkin et al., 8) ice cover, sea area 1 5 1 1 196 1965 197 1975 198 1985 199 1995 5 T 15 m, C Febrary March March T15 m Линейная (Febrary March) Warm year transport Cold year transport 5
Annual mean discharge of Amur River (red lines) and sea ice area over the Okhotsk Sea (blue lines). The lines are smoothed (3-year average) (Tachibana, Ogi, 9 (1)) Long-term discharge from Amur River (Novorotskii, 7 ()), below Seasonal variation of Amur River discharge discharge, m3/s 15 1 5 1 3 4 5 6 7 8 9 1 11 1 month 1 6
Waters temperature anomalies at South Kuril Islands area in 1961-199, June-October (Shatilina, 1996) (1), in 198-7, March (Zhigalov, 1)() 6 4 6 4 4 6 8 1 7 1961 196 1963 1964 1965 1967 1968 1969 197 1971 1973 1974 1975 1976 1977 1979 198 1981 198 1983 1985 1986 1987 1988 1989 Surface T HMS Yuzhno Kurilsk HMS Kurilsk 198 1984 1986 1988 199 199 1994 1996 1998 4 6 Annual mean discharge of Amur River (red lines) and sea ice area over the Okhotsk Sea (blue lines). The lines are smoothed (3- year average) (Tachibana, Ogi, 9). Bottom T
Annual mean discharge of Amur River (red lines) and sea ice area over the Okhotsk Sea (blue lines). The lines are smoothed (3-year average) (Tachibana, Ogi, 9). 1,8,6,4,,,4,6,8 1 Temperature, C Temperature anomaly in Bussol Strait area in 198-7 (Muktepavel, Shatilina, 7). Oceanic coast of Ithurup Island Bussol Strait 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 1 3 5 7 198 1984 1986 1988 199 199 1994 1996 1998 4 6 8
1,6 Sea surface temperature in the Okhotsk Sea in spring (left) and summer (right)(glebova et al., 9). 9 surface tamperature, C,8 Western Kamchatka 1974 1977 198 1983 1986 1989 199 1995 1998 1 4 7 surface temperature, C 8,5 8 Western Western Kamchatka Kamchatka 7,5 1974 1978 198 1986 199 1994 1998 6,5 9, surface temperature, C 1974 1977 198 1983 1986 1989 199 1995 1998 1 4 7 Northern area,5 surface temperature, C 8,5 Northern area 7,8 1974 1978 198 1986 199 1994 1998 6 3 1 surface temperature, C 1 Southern area 1974 1977 198 1983 1986 1989 199 1995 1998 1 4 7 surface temperature, C 9 Southern area 8 1974 1977 198 1983 1986 1989 199 1995 1998 1 4 7 Warming in 198-early199, cooling in -, warming after 3 9
The Pacific Decadal Oscillation (PDO) The Pacific Decadal Oscillation (PDO) warm phase cool phase 1 1 8 6 4 4 6 8 1 Forecast to the future decade cooling, may be by soft type 1 19 195 191 1915 19 195 193 1935 194 1945 195 1955 196 1965 197 1975 198 1985 199 1995 5 1
The atmospheric centers of action Long term trends in the change in repeatability of atmospheric processes over the Okhotsk Sea and ice cover in the cold season (October March) from 1974 to 7 (Glebova et al., 9). Forecast to the future decade cooling, but by soft type 11
Present status and forecasting In the 1s, the overall warming of the Okhotsk Sea waters, at least the northern area, is suggested by many processes such as reduced ice cover, increase in average values of SST over the sea, increase in Amur River runoff, and some other less noticeable processes. In the s, apparently, some cooling should be expected (Khen et al., 8, Ustinova et al., 4, Glebova, 7). 1
Fisheries impact: long-term trends of annual catches of Sakhalin-Hokkaido herring (1) and Terpeniye Bay s yellowfin sole () 1 1 8 6 4 1 7 6 5 4 3 1 9 1953 1957 1961 1965 1969 1973 1977 1981 1985 1989 1993 1997 1 5 thousand ton 187 1878 1886 1894 19 191 1918 196 1934 194 195 1958 1966 1974 198 199 1998 6 Fishery prohibition resource catch 13 Annual catch, thousand tons
Annual catches of walleye pollock in the Sea of Okhotsk: 1-Total Sea (with Hokkaido area), -Northern Okhotsk Sea, 3-Western Kamchatka, 4-Eastern Sakhalin (below South Kuril and adjacent waters), Walleye pollack (Sea of Okhotsk) 1 1,5 Catch, mln.tonn 1,,5 3 1965 197 1975 198 1985 199 1995 5 1 4 14
Some quantitative aspects of the Sea of Okhotsk for 198-th by total fishes biomass=35 mln. ton, year's production=17.5 mln. ton (Shuntov et al., 1997) Biomass and production of the main groups organisms in the Sea of Okhotsk in 198th The hydrobiont's group Вх1 6, ton Рх1 6, ton Phytoplankton - 151 Bacterial plankton - 5 Protozoa - 1 Non-predator zooplankton 314 5 Predator zooplankton 115 48 Non-predator zoobenthos 8,6 318 Predator zoobenthos 1,4,1 Pelagic fish 31,5 15,7 Demersal fish 3,5 1,7 Bottom invertebrate 1,5,5 Squids 7 Marine birds,1,4 Mammal,5,1 15
Fish species biomass ratio in pelagic communities of the northern Sea of Okhotsk in the last 198s, early 199s, last 199s (Shuntov et al., 1997), 1 walleye pollock, herring, 3 - others -1 - -3 Last 198s 1,1 93, 4,9 9,7 14,3 9,3 85,5,1 99, 9, 18, 7,4 9, 4, 1, 9 81, 3,3 78, 1, 94, 5 3,3 Early 199s 9,4 84, 3 8,3 5,9 43,3 1,3 53,9 11, 5,8 44,8 81,6 7,4 3, 7 8,8 46, 3 53, 7 15,5 Last 199s 4, 6,8 89, 1,3 4,1 85,6 3,6 1,5 77,7 78,5 18,7 13, 7 1,6 3,9 67,5 66, 3 19, 9 35, 3 54, 3,4 1,1 98, 5 1, 4 Biomass x1 tons 16
Composition and biomass of epipelagic fish communities in the Sea of Okhotsk (Dulepova, Merzlyakov, 7) biomass, thousand ton 16 14 1 1 8 6 4 biomass, thousand tons 14 1 1 8 6 4 Walleye pollack Pacific herring Pacific Capelin Other fish Salmons Northern smoothtongue Japaneese anchovy Other fish Northern Okhotsk Sea Southern Okhotsk Sea Annual catches of Japanese sardine in 1974-199 (Belayev, 3) Catches, ton 7 6 5 4 3 1 Japanese sardine 1974 1976 1978 198 198 1984 1986 1988 199 199 Japanese fishery area The Sea of Okhotsk South Kuril Islands Pacific Ocean 17
Annual abundance and biomass of walleye pollack spawning stock in the northern Okhotsk Sea (Ovsyannikov, 9) Abundance, bln. Ind. 18 16 14 1 1 8 6 4 1977, 1978 1981 1984 1986, 1987, 1988, 1989 199 1995 1995 1997 1997 1 9 8 7 6 5 4 3 1 Biomass, mln. tons 1984 1985 1986 1987 1988 1989 199 1991 199 1993 1994 1995 1996 1997 1998 1999 1 3 4 5 6 7 8 Abundance, bln. ind. Biomass, mln. tons Prevailed generation 1988 Abundant generation 18
Annual catches of Pacific herring in the far-eastern seas (Naumenko, 7) Okhotsk stock Korf-Karaginsk stock Eastern Bering Sea stock Gizhiginsk-Kamchatka stock Sakhalin-Hokkaido stock Others Okhotsk stock Annual dynamics of resources of Okhotsk herring in 1945-1985 (5-years smoothing) 19
Regular bottom trawl surveys areas in the Sea of Okhotsk 6 55 Amur water Kamchatka Peninsula 5 Sakhalin Island Sea of Okhotsk East Kamchatka Current 45 Soya Current Hokkaido Island Oyashio Current Pacific 4 135 14 145 15 155 16 165
Annual biomass of cottid-fishes (1), gadid-fishes (), flat-fishes (3), and all demersal fish (4) on west Kamchatka shelf, thousand ton (Ilyinskiy et al., 1) 16 14 1 1 8 6 4 Cottid-fish Gadid-fish Flat-fish All fish All fish Flat-fish 198 1986 1988 1989 1996 1997 1998 1999 1 1 5 7 8 9 1 Gadid-fish Cottid-fish 1
Some long-term trends of demersal fish biomass at Sakhalin and Kuril Islands 54 53 5 51 5 49 о. Сахалин average biomass per 1 sq. miles, ton 45 4 35 3 5 15 1 5 South Kuril R² =,93 1988 199 1 3 4 5 7 1 48 47 46 14 143 144
Average relative biomass of dominant species of fishes at South Kuril, ton/sq. mile 3 8 1 1988 199 1 3 4 5 7 1 Eleginus gracilis Gadus macrocephalus Theragra chalcogramma 6 4 1988 199 1 3 4 5 7 1 P. monopterigius H.lagocephalus Pleurogrammus azonus 15 6 1 4 5 Gymnocanthus detrisus Enophrys diceraus All cottid fish 1988 199 1 3 4 5 7 1 Myoxocephalus polyacanthocephalus Myoxocephalus jaok Pseudopleuronectes schrenki Cleisthenes herzensteini Glyptocephalus stelleri 1988 199 1 3 4 5 7 1 Lepidopsetta bilineata Myzopsetta herzensteini All flat fish 3
Dynamics of ice conditions, some atmospheric processes, and thermal regime of waters, intensity and direction of the main currents in the sea of Okhotsk in recent decades is in manifestly synchronous nature, allowing exploring the climate and oceanographic factors as a single integrated process, which has a decisive influence on the development of biological communities. Sakhalin Research Institute of Fisheries & Oceanography (SakhNIRO)