CLIMATIC ANOMALIES IN FAR EASTERN MARGINAL SEAS, BAIKAL LAKE BASIN AND THEIR LINKAGES

2017 ◽  
Author(s):  
Svetlana Shkorba ◽  
Svetlana Shkorba ◽  
Elena Dmitrieva ◽  
Elena Dmitrieva ◽  
Irina Mashkina ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Time Scales ◽  
Lake Basin ◽  
Baikal Lake ◽  
Climatic Indices ◽  
Marginal Seas ◽  
Northeast Pacific ◽  
The Pacific ◽  
South Siberia ◽  
Asian Pacific

Winter climatic anomalies of various time scales in the Japan, Okhotsk seas and Baikal Lake Basin are revealed and compared with anomalies in the Pacific, Indian and Arctic oceans. Time series of ice extent in the Japan and Okhotsk seas, ice thickness and seasonal duration of the ice cover in the Baykal Lake, as well as Hadley SST, surface heat fluxes, wind velocity, atmospheric pressure fields (SLP) and different climatic indices are analyzed. The decadal climate anomalies in the Japan and Okhotsk seas in mid winter, as compared to the Northeast Pacific and South Siberia regions, could have a reversed phase. Alternating cold/warm decadal anomalies in different longitude zones of the North Asian Pacific are accompanied by alternating meridional wind and SLP anomalies at temperate latitudes. Alternating zones of inversed anomalies in temperate latitudes of the Asian Pacific are related to teleconnections with anomalies in both Arctic and Indo-Pacific oceans. Negative SSTA in eastern/central tropical-equatorial Pacific and positive SSTA in El Nino area accompanies rise of northern wind and ice extent in the Okhotsk/Japan Seas in mid-winter. The best predictors of the high cold anomaly in February in the western subarctic Pacific and marginal seas are reduction of the SST and net heat flux from the atmosphere to the ocean in north-eastern and central North Pacific during warm period of a previous year. At the multidecadal time scale the warming/cooling in the Northeast Pacific accompany winter warming/cooling in the Baykal Lake area during all period of observation. At interdecadal time scales the significant link of winter climate oscillations in South Siberia (Baikal Lake Basin) is found with SSTA oscillations in the equatorial region of the Indian Ocean and certain areas of the Pacific Ocean. The linkages of anomalies in the Baikal Lake Basin, Okhotsk, Japan Seas with regional anomalies in some key areas of the Pacific and Indian Oceans, related to the atmospheric centers of action are more stable than that with climatic indices. After climate regime shift in late 70s warm decadal anomaly in both Lake Baykal Basin and Indian Ocean in boreal winter accompany high positive anomaly of the Arctic Oscillation. Scenarios of extreme anomalies in the Baikal Lake Basin and Subarctic Pacific marginal area are also presented.

CLIMATIC ANOMALIES IN FAR EASTERN MARGINAL SEAS, BAIKAL LAKE BASIN AND THEIR LINKAGES

2017 ◽  
Author(s):  
Svetlana Shkorba ◽  
Svetlana Shkorba ◽  
Elena Dmitrieva ◽  
Elena Dmitrieva ◽  
Irina Mashkina ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Time Scales ◽  
Lake Basin ◽  
Baikal Lake ◽  
Climatic Indices ◽  
Marginal Seas ◽  
Northeast Pacific ◽  
The Pacific ◽  
South Siberia ◽  
Asian Pacific

Winter climatic anomalies of various time scales in the Japan, Okhotsk seas and Baikal Lake Basin are revealed and compared with anomalies in the Pacific, Indian and Arctic oceans. Time series of ice extent in the Japan and Okhotsk seas, ice thickness and seasonal duration of the ice cover in the Baykal Lake, as well as Hadley SST, surface heat fluxes, wind velocity, atmospheric pressure fields (SLP) and different climatic indices are analyzed. The decadal climate anomalies in the Japan and Okhotsk seas in mid winter, as compared to the Northeast Pacific and South Siberia regions, could have a reversed phase. Alternating cold/warm decadal anomalies in different longitude zones of the North Asian Pacific are accompanied by alternating meridional wind and SLP anomalies at temperate latitudes. Alternating zones of inversed anomalies in temperate latitudes of the Asian Pacific are related to teleconnections with anomalies in both Arctic and Indo-Pacific oceans. Negative SSTA in eastern/central tropical-equatorial Pacific and positive SSTA in El Nino area accompanies rise of northern wind and ice extent in the Okhotsk/Japan Seas in mid-winter. The best predictors of the high cold anomaly in February in the western subarctic Pacific and marginal seas are reduction of the SST and net heat flux from the atmosphere to the ocean in north-eastern and central North Pacific during warm period of a previous year. At the multidecadal time scale the warming/cooling in the Northeast Pacific accompany winter warming/cooling in the Baykal Lake area during all period of observation. At interdecadal time scales the significant link of winter climate oscillations in South Siberia (Baikal Lake Basin) is found with SSTA oscillations in the equatorial region of the Indian Ocean and certain areas of the Pacific Ocean. The linkages of anomalies in the Baikal Lake Basin, Okhotsk, Japan Seas with regional anomalies in some key areas of the Pacific and Indian Oceans, related to the atmospheric centers of action are more stable than that with climatic indices. After climate regime shift in late 70s warm decadal anomaly in both Lake Baykal Basin and Indian Ocean in boreal winter accompany high positive anomaly of the Arctic Oscillation. Scenarios of extreme anomalies in the Baikal Lake Basin and Subarctic Pacific marginal area are also presented.

Intraseasonal-to-Interannual Variability of South Indian Ocean Sea Level and Thermocline: Remote versus Local Forcing

2012 ◽  
Vol 42 (4) ◽  
pp. 602-627 ◽  
Author(s):  
Laurie L. Trenary ◽  
Weiqing Han
Keyword(s):  
Indian Ocean ◽  
Interannual Variability ◽  
Sea Level ◽  
Time Scales ◽  
Ekman Pumping ◽  
Remote Forcing ◽  
South Indian ◽  
The Pacific ◽  
The Indian Ocean ◽  
Thermocline Variability

Abstract The relative importance of local versus remote forcing on intraseasonal-to-interannual sea level and thermocline variability of the tropical south Indian Ocean (SIO) is systematically examined by performing a suite of controlled experiments using an ocean general circulation model and a linear ocean model. Particular emphasis is placed on the thermocline ridge of the Indian Ocean (TRIO; 5°–12°S, 50°–80°E). On interannual and seasonal time scales, sea level and thermocline variability within the TRIO region is primarily forced by winds over the Indian Ocean. Interannual variability is largely caused by westward propagating Rossby waves forced by Ekman pumping velocities east of the region. Seasonally, thermocline variability over the TRIO region is induced by a combination of local Ekman pumping and Rossby waves generated by winds from the east. Adjustment of the tropical SIO at both time scales generally follows linear theory and is captured by the first two baroclinic modes. Remote forcing from the Pacific via the oceanic bridge has significant influence on seasonal and interannual thermocline variability in the east basin of the SIO and weak impact on the TRIO region. On intraseasonal time scales, strong sea level and thermocline variability is found in the southeast tropical Indian Ocean, and it primarily arises from oceanic instabilities. In the TRIO region, intraseasonal sea level is relatively weak and results from Indian Ocean wind forcing. Forcing over the Pacific is the major cause for interannual variability of the Indonesian Throughflow (ITF) transport, whereas forcing over the Indian Ocean plays a larger role in determining seasonal and intraseasonal ITF variability.

scholarly journals Unraveling Causes for the Changing Behavior of the Tropical Indian Ocean in the Past Few Decades

2018 ◽  
Vol 31 (6) ◽  
pp. 2377-2388 ◽  
Author(s):  
Lei Zhang ◽  
Weiqing Han ◽  
Frank Sienz
Keyword(s):  
Indian Ocean ◽  
Time Scales ◽  
Climate Models ◽  
Decadal Variability ◽  
Global Climate ◽  
Tropical Indian Ocean ◽  
Volcanic Eruptions ◽  
Warming Trend ◽  
External Forcing ◽  
The Pacific

Observations show that decadal (10–20 yr) to interdecadal (>20 yr) variability of the tropical Indian Ocean (TIO) sea surface temperature (SST) closely follows that of the Pacific until the 1960s. Since then, the TIO SST exhibits a persistent warming trend, whereas the Pacific SST shows large-amplitude fluctuations associated with the interdecadal Pacific oscillation (IPO), and the decadal variability of the TIO SST is out of phase with that of the Pacific after around 1980. Here causes for the changing behavior of the TIO SST are explored, by analyzing multiple observational datasets and the recently available large-ensemble simulations from two climate models. It is found that on interdecadal time scales, the persistent TIO warming trend is caused by emergence of anthropogenic warming overcoming internal variability, while the time of emergence occurs much later in the Pacific. On decadal time scales, two major tropical volcanic eruptions occurred in the 1980s and 1990s causing decadal SST cooling over the TIO during which the IPO was in warm phase, yielding the out-of-phase relation. The more evident fingerprints of external forcing in the TIO compared to the Pacific result from the much weaker TIO internal decadal–interdecadal variability, making the TIO prone to the external forcing. These results imply that the ongoing warming and natural external forcing may make the Indian Ocean more active, playing an increasingly important role in affecting regional and global climate.

CLIMATIC REGIME CHANGE IN THE ASIAN PACIFIC REGION, INDIAN AND SOUTHERN OCEANS AT THE END OF THE 20TH CENTURY

2017 ◽  
Author(s):  
Vladimir Ponomarev ◽  
Vladimir Ponomarev ◽  
Elena Dmitrieva ◽  
Elena Dmitrieva ◽  
Svetlana Shkorba ◽  
...  
Keyword(s):  
20Th Century ◽  
Regime Change ◽  
World Ocean ◽  
Boreal Summer ◽  
Climate Regime ◽  
Precipitation Decrease ◽  
Recent Climate ◽  
South Siberia ◽  
Asian Pacific ◽  
Southern Oceans

Multiple scale climate variability in Asia of temperate and high latitudes, Pacific, Indian and South Oceans, their features and linkages are studied by using statistical analyses of monthly mean time series of Hadley, Reynolds SST, surface net heat flux (Q), atmospheric pressure (SLP), air temperature (SAT) from NCEP NCAR reanalyses (1948-2015). Three multidecadal climatic regimes were revealed for the whole area studied by using cluster analyses via Principal Components of differences between values of Q, SLP, SAT in tropical and extratropical regions of the Asian Pacific, Indian and Southern Oceans. The climate regime change in 70s of the 20th century in this area is confirmed by this method. It is also found that the climate regime is significantly changed at the end of the 20th century in both same area and World Ocean. The characteristic features of recent climate regime after 1996-1998 are SLP increase in the central extratropic area of Indian Ocean, North and South Pacific being prevailing in boreal winter. It is accompanying SLP increase and precipitation decrease in South Siberia and Mongolia prevailing in boreal summer. Inversed SLP and precipitation anomaly associated with increase of cyclone activity and extreme events in the land-ocean marginal zones including Southern Ocean, eastern Arctic, eastern Indian, western and eastern Pacific margins. It is known that low frequency PDO phase is also changed at the same time.

CLIMATIC REGIME CHANGE IN THE ASIAN PACIFIC REGION, INDIAN AND SOUTHERN OCEANS AT THE END OF THE 20TH CENTURY

2017 ◽  
Author(s):  
Vladimir Ponomarev ◽  
Vladimir Ponomarev ◽  
Elena Dmitrieva ◽  
Elena Dmitrieva ◽  
Svetlana Shkorba ◽  
...  
Keyword(s):  
20Th Century ◽  
Regime Change ◽  
World Ocean ◽  
Boreal Summer ◽  
Climate Regime ◽  
Precipitation Decrease ◽  
Recent Climate ◽  
South Siberia ◽  
Asian Pacific ◽  
Southern Oceans

Multiple scale climate variability in Asia of temperate and high latitudes, Pacific, Indian and South Oceans, their features and linkages are studied by using statistical analyses of monthly mean time series of Hadley, Reynolds SST, surface net heat flux (Q), atmospheric pressure (SLP), air temperature (SAT) from NCEP NCAR reanalyses (1948-2015). Three multidecadal climatic regimes were revealed for the whole area studied by using cluster analyses via Principal Components of differences between values of Q, SLP, SAT in tropical and extratropical regions of the Asian Pacific, Indian and Southern Oceans. The climate regime change in 70s of the 20th century in this area is confirmed by this method. It is also found that the climate regime is significantly changed at the end of the 20th century in both same area and World Ocean. The characteristic features of recent climate regime after 1996-1998 are SLP increase in the central extratropic area of Indian Ocean, North and South Pacific being prevailing in boreal winter. It is accompanying SLP increase and precipitation decrease in South Siberia and Mongolia prevailing in boreal summer. Inversed SLP and precipitation anomaly associated with increase of cyclone activity and extreme events in the land-ocean marginal zones including Southern Ocean, eastern Arctic, eastern Indian, western and eastern Pacific margins. It is known that low frequency PDO phase is also changed at the same time.

Vietnam in the Indo-Pacific Region: Perception, Position and Perspectives

2021 ◽  
pp. 097492842110050
Author(s):  
Nguyen Le Thy Thuong ◽  
Nguyen Thi Oanh
Keyword(s):  
Swot Analysis ◽  
Geographic Area ◽  
Common Interest ◽  
Pacific Region ◽  
Analysis Model ◽  
Common Space ◽  
The Pacific ◽  
The World ◽  
State Behaviour ◽  
Asian Pacific

The Indo-Pacific region is an area adjacent to some oceans and the gateway that connects the great power and small countries to the world; this region is always considered by Vietnam as a key strategic geographic area, having direct impacts on national security, position and its role in this region. While big powers have different perceptions to the Indo-Pacific region, as a country occupying an important geographic position in the Pacific region, Vietnam shares a common vision of an open and rule-based area, and a common interest in maintaining peace, stability and prosperity as well as building a common space for coexistence and development with the belief that the Indo-Asian-Pacific is large enough for every nation to grow and prosper. This article finds out that recent changes in the Indo-Pacific region in geopolitics, economics, security and national defence have made many countries, including Vietnam, to redefine their global and regional policies to refresh their strategic perceptions. Vietnam has its own perception, position, approach and national orientations, which is shaping its state behaviour and perspectives in this geopolitical vibrant Indo-Pacific region. Besides, this article uses the SWOT analysis model to determine the challenges, strengths and weaknesses of Vietnam in the Indo-Pacific region. Moreover, while the future of the Indo-Pacific in a post-COVID-19 pandemic world remains filled with uncertainty and economic challenges, the crisis also presents an opportunity for Vietnam to re-evaluate its position. Today, Vietnam always maintains its foreign policy of independence, self-reliance, multilateralism and diversification of international relations, which attaches great importance to enhancing multi-faceted cooperation with countries in the Indo-Pacific region. Thus, with its own perception and geostrategic advantage, Vietnam—a developing country in the region and in the world with relatively stable economic growth, pursuing rules and order will be a positive factor for a stable, peaceful and prosperous development in the region.

scholarly journals Research Gap Analysis of Remote Sensing Application in Fisheries: Prospects for Achieving the Sustainable Development Goals

2021 ◽  
Vol 13 (5) ◽  
pp. 1013
Author(s):  
Kuo-Wei Yen ◽  
Chia-Hsiang Chen
Keyword(s):  
Sustainable Development ◽  
Indian Ocean ◽  
Atlantic Ocean ◽  
The Sustainable Development ◽  
The North ◽  
The Pacific ◽  
Development Goals ◽  
The Indian Ocean ◽  
The Pacific Ocean ◽  
Research Hotspots

Remote sensing (RS) technology, which can facilitate the sustainable management and development of fisheries, is easily accessible and exhibits high performance. It only requires the collection of sufficient information, establishment of databases and input of human and capital resources for analysis. However, many countries are unable to effectively ensure the sustainable development of marine fisheries due to technological limitations. The main challenge is the gap in the conditions for sustainable development between developed and developing countries. Therefore, this study applied the Web of Science database and geographic information systems to analyze the gaps in fisheries science in various countries over the past 10 years. Most studies have been conducted in the offshore marine areas of the northeastern United States of America. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. This study also found that research hotspots of satellite RS applications in fisheries were mainly conducted in (1) the northeastern sea area in the United States, (2) the high seas area of the North Atlantic Ocean, (3) the surrounding sea areas of France, Spain and Portugal, (4) the surrounding areas of the Indian Ocean and (5) the East China Sea, Yellow Sea and Bohai Bay sea areas to the north of Taiwan. A comparison of publications examining the three major oceans indicated that the Atlantic Ocean was the most extensively studied in terms of RS applications in fisheries, followed by the Indian Ocean, while the Pacific Ocean was less studied than the aforementioned two regions. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. The Atlantic Ocean and the Indian Ocean have been the subjects of many local in-depth studies; in the Pacific Ocean, the coastal areas have been abundantly investigated, while offshore local areas have only been sporadically addressed. Collaboration and partnership constitute an efficient approach for transferring skills and technology across countries. For the achievement of the sustainable development goals (SDGs) by 2030, research networks can be expanded to mitigate the research gaps and improve the sustainability of marine fisheries resources.

scholarly journals Long-term ocean acidification trends in coastal waters around Japan

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiroshi Ishida ◽  
Ryosuke S. Isono ◽  
Jun Kita ◽  
Yutaka W. Watanabe
Keyword(s):  
Pacific Ocean ◽  
Ocean Acidification ◽  
Sea Of Japan ◽  
Ocean Current ◽  
The Sea Of Japan ◽  
Marginal Seas ◽  
The Pacific ◽  
Activity Measurements ◽  
The Pacific Ocean

AbstractThis study examines long-term ocean pH data to evaluate ocean acidification (OA) trends at two coastal research institutions located on the Sea of Japan and the Pacific Ocean. These laboratories are located away from the influences of large rivers and major industrial activity. Measurements were performed daily for the past 30 years (1980s–2010s). The average annual ocean pH for both sites showed generally negative trends. These trends were – 0.0032 and – 0.0068 year–1 (p < 0.001) at the Sea of Japan and Pacific Ocean sites, respectively. The trends were superimposed onto approximately 10-year oscillations, which appear to synchronize with the ocean current periodicity. At the Sea of Japan site, the ocean pH in the summer was higher, and the rate of OA was higher than during other seasons. Our results suggest that seasonality and ocean currents influence OA in the coastal areas of open oceans and can affect the coastal regions of marginal seas.

scholarly journals Sources of Tropical Subseasonal Skill in the CFSv2

2020 ◽  
Vol 148 (4) ◽  
pp. 1553-1565 ◽  
Author(s):  
Carl J. Schreck ◽  
Matthew A. Janiga ◽  
Stephen Baxter
Keyword(s):  
Indian Ocean ◽  
Low Frequency ◽  
Equatorial Pacific ◽  
Convectively Coupled Equatorial Waves ◽  
Subseasonal Variability ◽  
The Pacific ◽  
Fourier Filtering ◽  
The Indian Ocean ◽  
Rainfall Anomalies ◽  
Combined Data

Abstract This study applies Fourier filtering to a combination of rainfall estimates from TRMM and forecasts from the CFSv2. The combined data are filtered for low-frequency (LF, ≥120 days) variability, the MJO, and convectively coupled equatorial waves. The filtering provides insight into the sources of skill for the CFSv2. The LF filter, which encapsulates persistent anomalies generally corresponding with SSTs, has the largest contribution to forecast skill beyond week 2. Variability within the equatorial Pacific is dominated by its response to ENSO, such that both the unfiltered and the LF-filtered forecasts are skillful over the Pacific through the entire 45-day CFSv2 forecast. In fact, the LF forecasts in that region are more skillful than the unfiltered forecasts or any combination of the filters. Verifying filtered against unfiltered observations shows that subseasonal variability has very little opportunity to contribute to skill over the equatorial Pacific. Any subseasonal variability produced by the model is actually detracting from the skill there. The MJO primarily contributes to CFSv2 skill over the Indian Ocean, particularly during March–May and MJO phases 2–5. However, the model misses opportunities for the MJO to contribute to skill in other regions. Convectively coupled equatorial Rossby waves contribute to skill over the Indian Ocean during December–February and the Atlantic Ocean during September–November. Convectively coupled Kelvin waves show limited potential skill for predicting weekly averaged rainfall anomalies since they explain a relatively small percent of the observed variability.

The Role of Intraseasonal Variability in the Nature of Asian Monsoon Precipitation

2007 ◽  
Vol 20 (17) ◽  
pp. 4402-4424 ◽  
Author(s):  
Carlos D. Hoyos ◽  
Peter J. Webster
Keyword(s):  
Indian Ocean ◽  
Time Scales ◽  
Temporal Variability ◽  
Asian Monsoon ◽  
Monsoon Rainfall ◽  
Mountain Range ◽  
Monsoon Precipitation ◽  
The West ◽  
The Mean ◽  
Rainfall Estimates

Abstract The structure of the mean precipitation of the south Asian monsoon is spatially complex. Embedded in a broad precipitation maximum extending eastward from 70°E to the northwest tropical Pacific Ocean are strong local maxima to the west of the Western Ghats mountain range of India, in Cambodia extending into the eastern China Sea, and over the eastern tropical Indian Ocean and the Bay of Bengal (BoB), where the strongest large-scale global maximum in precipitation is located. In general, the maximum precipitation occurs over the oceans and not over the land regions. Distinct temporal variability also exists with time scales ranging from days to decades. Neither the spatial nor temporal variability of the monsoon can be explained simply as the response to the cross-equatorial pressure gradient force between the continental regions of Asia and the oceans of the Southern Hemisphere, as suggested in classical descriptions of the monsoon. Monthly (1979–2005) and daily (1997–present) rainfall estimates from the Global Precipitation Climatology Project (GPCP), 3-hourly (1998–present) rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) microwave imager (TMI) estimates of sea surface temperature (SST), reanalysis products, and satellite-determined outgoing longwave radiation (OLR) data were used as the basis of a detailed diagnostic study to explore the physical basis of the spatial and temporal nature of monsoon precipitation. Propagation characteristics of the monsoon intraseasonal oscillations (MISOs) and biweekly signals from the South China Sea, coupled with local and regional effects of orography and land–atmosphere feedbacks are found to modulate and determine the locations of the mean precipitation patterns. Long-term variability is found to be associated with remote climate forcing from phenomena such as El Niño–Southern Oscillation (ENSO), but with an impact that changes interdecadally, producing incoherent responses of regional rainfall. A proportion of the interannual modulation of monsoon rainfall is found to be the direct result of the cumulative effect of rainfall variability on intraseasonal (25–80 day) time scales over the Indian Ocean. MISOs are shown to be the main modulator of weather events and encompass most synoptic activity. Composite analysis shows that the cyclonic system associated with the northward propagation of a MISO event from the equatorial Indian Ocean tends to drive moist air toward the Burma mountain range and, in so doing, enhances rainfall considerably in the northeast corner of the bay, explaining much of the observed summer maximum oriented parallel to the mountains. Similar interplay occurs to the west of the Ghats. While orography does not seem to play a defining role in MISO evolution in any part of the basin, it directly influences the cumulative MISO-associated rainfall, thus defining the observed mean seasonal pattern. This is an important conclusion since it suggests that in order for the climate models to reproduce the observed seasonal monsoon rainfall structure, MISO activity needs to be well simulated and sharp mountain ranges well represented.

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