Download pices xv - North Pacific Marine Science Organization

PICES XV
W5-3249
Oral
The response of marine environment in the offshore area of China and its adjacent
ocean to recent global climate change
Rong-Shuo Cai1, Ji-Long Chen2 and Rong-Hui Huang2
1
2
Key Laboratory of Global Change and Marine-Atmospheric Chemistry, State Oceanic Administration (SOA), Xiamen 361005;
The Third Institute of Oceanography, SOA, Xiamen, 361005, PR China. E-mail: [email protected]
Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Science, Beijing, 100080, PR China
Due to the severity of impact of global climate warming on marine environment and ecosystem and sustainable
development of economy and society, the impacts of global climate change for recent 50 years on winter and
summer wind field near sea surface, sea surface zonal and meridional wind stresses and sea surface temperature
(SST) in the offshore area of China, including the Bohai Sea, the Yellow Sea, the East China Sea and the South
China Sea, and its adjacent ocean, mainly including the tropical and subtropical western Pacific, are analyzed by
using the wind data from ERA-40 reanalysis data, the high-resolution reanalysis data of ocean climate such as
HadISST and SODA (Simple Ocean Data Assimilation) and so on. The analyzed results show that due to the
impact of global climate warming, the winter and summer monsoon flows became weak over the offshore area
of China and its adjacent Ocean after 1976, which caused the weakening of winter and summer sea surface wind
stresses, especially the meridional sea surface wind stresses, and obvious increase of SST in the area. Moreover,
the results also show that the weakening of winter and summer sea surface wind stresses and the increase of SST
are particularly significant in the East China Sea. The weakening of winter and summer sea surface wind
stresses and the warming of SST in the offshore area of China these can provide a favorable marine environment
for the frequent occurrence of red tide in the offshore area of China. Besides, from variation of the distributions
of circulation divergences over the offshore area of China, it can be clearly seen that after 1976, the circulation
divergences over this area intensified, which were not helpful to the formation of upwelling flow in the offshore
area of China. It will have an influence on the transportation of nutrients in the coastal water. In order to
promote the research on the response and adaptation of marine environment and ecosystem in the offshore area
of China to global climate change, some scientific problems on this aspect, which urgently need to study, are
also proposed in this paper.
PICES XV
W5-2774
Invited
Managing, using and expanding the IPCC database of climate model output
Curtis Covey
Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, LLNL Mail Code L-103, 7000 East
Avenue, Livermore, CA, 94550, U.S.A. E-mail: [email protected]
Our program at Livermore has accepted a request from the Intergovernmental Panel on Climate Change to
assemble and manage a database of output from coupled ocean-atmosphere general circulation models. The
output includes both retrospective simulations of 20th century climate evolution and predictions of 21st century
climate change under a variety of emissions scenarios. Although it was originally created to help prepare the
IPCC's 2007 assessment report, the database has a variety of other uses and is open to any interested scientist. It
contains 27 Terabytes of data comprising output from 22 different models. To date we have over 600 registered
users, who have produced over 150 scientific publications involving the data. I will talk about my experience
helping to manage the database and using its contents, as well as plans for adding interactive land and ocean
biogeochemistry to the climate models contributing to a new database.
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PICES XV
W5-3202
Oral
Temperature and salinity along Line-P: Fifty years of observations
William Crawford1, Jake Galbraith2 and Nick Bolingbroke1
1
2
Institute of Ocean Sciences, Fisheries and Oceans Canada, P.O. Box 6000, Sidney, BC, V8L 4B2, Canada
E-mail: [email protected]
920 Haltain St., Victoria, BC, V8R 2L5, Canada
Accurate profiles of ocean temperature and salinity have been collected along Line-P since the 1950s, forming
the Line-P series that extends from coastal waters out 1420 kilometres into the Gulf of Alaska. Data along these
stations were sampled from 1950s to 1981 by Canadian Department of Transport weatherships on their way
from Victoria, Canada, to Ocean Station Papa at 50°N, 145°W. Canadian Fisheries and Oceans research vessels
took over sampling in 1981 when the weatherships program ended. Throughout these years the ocean
measurements have been managed by scientists of the Pacific Biological Station in Nanaimo, BC, and then by
scientists of Fisheries and Oceans Canada at the Institute of Ocean Sciences in Sidney, BC. We used archived
measurements of temperature and salinity to compute climatology of the seasonal cycle of these properties, as
well as seawater density, at standard depths along Line-P. From these we computed time series anomalies of
temperature and salinity averaged over several depth layers along Line-P. Results are presented graphically as
Hovmøller plots, extending in time from 1950 to 2005 and in distance from Station P1 to P26 (OSP). Major
climate events such as the sudden warming in 1976/77 and cooling in 1997/98 are clearly present in these plots.
Density differences between near-surface waters and the 100-m layer have increased over the past 50 years.
Interestingly, the top 150 metres of the ocean along Line-P in 1999 to 2002 were as cold as ever observed
previously, despite the general warming since 1950. Since 2001 the top 100 metres have been significantly
fresher than the 50-year average. These observations will continue to be collected, and will form a significant
contribution to ocean climate programs.
PICES XV
W5-3179
Oral
Highlights from recent publications describing climate projections for the North Pacific
Michael G. Foreman
Institute of Ocean Sciences, Fisheries and Oceans Canada, P.O. Box 6000, Sidney, BC, V8L 4B2, Canada
E-mail: [email protected]
The submission of climate model projections for the upcoming IPCC 4 th assessment report has provided a
unique opportunity for intercomparison and the calculation of ensemble averages. Publications are beginning to
appear describing some of these results and more are expected soon. In this presentation, we will highlight
some specific findings for the North Pacific and describe their applicability to the objectives of PICES Working
Group 20.
PICES XV
W5-3190
Oral
Overview of the present state and future projection of North Pacific climate simulated
by CCSR/NIES/FRCGC global coupled models
Hiroyasu Hasumi1 and Takashi T. Sakamoto2
1
2
Center for Climate System Research, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8568, Japan
E-mail: [email protected]
Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawaku, Yokohama, Kanagawa, 236-0001, Japan
The research consortium of the Center for Climate System Research (CCSR), the National Institute for
Environmental Studies (NIES), and the Frontier Research Center for Global Change (FRCGC) submitted two
sets of climate projection results to IPCC AR4, using global coupled models with two different resolutions. The
higher resolution model is made up of T106 (~1) atmosphere and eddy-permitting ocean, while the lower
resolution version incorporates T42 (~3) atmosphere and coarse-resolution (~1) ocean. The two models
exhibit different responses to global warming in some respects. In order to answer the question of where and
how resolution matters, we also conducted present climate simulations using two more models: one with a
higher resolution atmosphere and lower resolution ocean, and the other with a lower resolution atmosphere and
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higher resolution ocean. Here we discuss resolution dependence of the present state and future projections of
the CCSR/NIES/FRCGC global coupled models, with a focus on the North Pacific region.
PICES XV
W5-3006
Oral
Decadal trend of dissolved oxygen in the North Pacific along 165ºE – A preview
Masao Ishii1, Takayuki Tokieda1, Shu Saito1, Takashi Midorikawa1, Shinji Masuda2, and Akira Nakadate2
1
2
Geochemical Research Department, Meteorological Research Institute, 1-1 Nagammine, Tsukuba, Ibaraki, 305-0052, Japan
E-mail: [email protected]
Global Environment and Marine Department, Japan Meteorological Agency, 1-3-4 Otemachi, Chiyoda, Tokyo, 100-8122, Japan
An increase of total inorganic carbon (TCO2) during the last decade has been observed in the upper layer of the
western North Pacific along 137ºE and 165ºE, and in the thermocline of the western equatorial Pacific. It is
primarily ascribed to the invasion of the anthropogenic CO 2 into the ocean interior, but the concurrent change in
the dissolved oxygen (DO) suggests that changes in ocean circulation and/or biogeochemistry is also playing an
important role in changing the TCO2 inventory. The Japan Meteorological Agency has been conducting routine
observations of a hydrographic section in the top 2000m of water along 165ºE between 50ºN and 28ºN, and
between 28ºN and 3ºS once or twice a year since 1997. The observed parameters include chemical components
such as DO. Routine high-quality TCO2 measurements were also started in 2003 at several stations along 165ºE.
We will present some preliminary results showing trends in DO and TCO2 in these regions.
PICES XV
W5-3191
Oral
Seasonal long-term variation of temperature in Korean waters
Hee-Dong Jeong, In-Seong Han, Ig-Chan Pang, Ki-Tack Seong, Woo-Jin Go, Sang-Woo Kim, Won-Deuk
Yoon, Yong-Kyu Choi and Jun-Yong Yang
National Fisheries Research and Development Institute, 408-1, Shirang-Ri, Gijang-gun, Busan, 619-705, Republic of Korea
E-mail: [email protected]
Serial oceanographic investigations in Korean waters have been carried out by NFRDI (National Fisheries
Research and Development Institute) over 37 years from 1968 to 2004. In this study, we examine seasonal and
annual long-term variations of temperature and the long-term trend of annual temperature. The data show that
the annual mean sea surface temperature (SST) has clearly increased by about 0.9°. The increase of SST was
about 0.7° in August and was about 1.35° in February. This indicates that the annual amplitude of SST variation
would be decreased by the strong increasing trend in winter temperatures. Korean waters can be geographically
divided into three seas; East Sea, South Sea and Yellow Sea. The trends of SST increase for the three seas in
August and February were found to be 0.47° and 1.47° in the East Sea; 0.81° and 0.70° in the South Sea; and
0.71° and 1.45° in the Yellow Sea, respectively. The annual amplitude of SST decreased by about 0.63° and
0.07° in the East Sea and Yellow Sea respectively, but it slightly increased about 0.11° in the South Sea during
last 37 years.
PICES XV
W5-3011
Invited
Significance of ocean’s response to climate warming in the global carbon cycle
Michio Kawamiya, Chisato Yoshikawa, Tomomichi Kato and Taroh Matsuno
Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25, Showamachi, Kanazawaku, Yokohama, 235-0001, Japan. E-mail: [email protected]
It has been recognized through modeling efforts that climate – carbon cycle interactions may form a positive
feedback loop for the global warming. The actual extent of the feedback is, however, strongly model dependent.
This situation necessitates an organized activity to compare results from various models and discuss what causes
such differences between models. An international project C4MIP (Coupled Carbon-Cycle Climate Model
Inter-comparison Project) has been established in order to facilitate such comparative studies (Friedlingstein et
al., in press) and discussions made under C4MIP are likely to be reflected in the 4 th assessment report of IPCC
(Intergovernmental Panel on Climate Change). All the eleven models participating in C4MIP show an
agreement in that CO2 uptake by both the land and the ocean is reduced due to future warming, although the
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increase of atmospheric CO2 concentration varies among models between 20ppm and 200ppm by the end of the
21st century. Eight models attribute most of the changes to the land, while three attribute it comparably to both
the land and the ocean; the role of the ocean does not appear to be dominant in the climate – carbon cycle
feedback. However, there are some inconsistencies between results from ocean carbon cycle models and those
from observation-based studies. For example, air-sea CO2 fluxes obtained by inversion techniques and carbon
isotope analysis yield much larger interannual variations than those by computed by forward numerical models.
Such problems may indicate that the oceanic feedback in the climate – carbon cycle system is currently
underestimated.
PICES XV
W5-3064
Oral
Estimation of design wave height through long-term simulation of sea states for the
North East Asia regional seas
Dong-Young Lee, K.C. Jun
Korea Ocean Research and Development Institute, P.O. Box 29, Ansan, 425-600, Republic of Korea. E-mail: [email protected]
Two types of long term wave climate information are desired for many marine and coastal applications
especially for the design of coastal structures: the design waves and operational waves. In conventional
methods of design criteria estimation, it is assumed that the climate is stationary and the statistics and extreme
analysis of long-term measured or hindcasted data can be used in statistical predictions for the future. However,
such a steady state assumption is questionable due to global climate change.
Since the availability of field wave data for the waters around Korean peninsula is limited in its ability to cover
a significant period of time so as to provide reliable wave statistics, the wave climate information needs to be
generated by means of long-term wave hindcasting using available meteorological data. Design wave heights
for the return periods of 30, 50 and 100 years for 16 directions at each grid point of a grid with 18 km resolution
for the waters around Korean peninsula have been estimated by means of extreme wave analysis using the
detailed wave simulation data for major typhoons that affected Korea since 1951 and continuous hindcasted
wave data since 1979.
Methods of extreme statistical analysis that consider recent extreme events like typhoon Maemi in 2003 were
evaluated for more stable results of design wave height estimation for the return periods of 30-50 years, which is
commonly applied in designing coastal structures like breakwaters. The impact of global climate change in the
estimation of design wave height for the return periods of 30 and 50 years was analyzed and will be discussed
PICES XV
W5-2906
Invited
A modeling study of interannual to decadal variability in Equatorial Pacific
biogeochemistry and ecosystems
Keith B. Rodgers1, Christophe Menkes2, Thomas Gorgues2, Laurent Bopp3 and Olivier Aumont2,4
1
2
3
4
Program in Atmospheric and Oceanic Sciences, Princeton University, 300 Forrestal Road, Sayre Hall, Princeton, NJ, 08544-0710, U.S.A.
E-mail: [email protected]
LOCEAN, T 45-55, 4E, 4 pl Jussieu – boite 100, 75252 Paris Cedex 05, France
LSCE, CEA Saclay, Bat. 712 – Orme, F-91191, Gif-sur-Yvette Cedex, France
Centre IRD de Bretagne, BP 70, 29280 Plouzané, France
A three dimensional ocean circulation model (the ORCA2 configuration of OPA), which has a
foodweb/biogeochemistry model (PISCES) embedded in it, and which has been forced with NCEP reanalysis
fluxes, has been used to study variability in the supply of nutrients to the euphotic zone/upwelling regions of the
eastern Equatorial Pacific. Our main finding is that the model exhibits a significant decrease in Fe, Chl, and
NO3 concentrations after 1976 for the upwelling regions of the Eastern Equatorial Pacific. For Fe and Chl, this
shift in the mean state is shown to reflect a large change in the amplitude of the seasonal cycle, with seasonally
maximum values having been larger for the earlier period. For NO 3, there is more of a change in the mean state.
These changes can be understood as being due to the interplay of two mechanisms. First, the s0=25.0 potential
density surface corresponding to the core of the Equatorial Undercurrent (EUC) was deeper in the western
Equatorial Pacific during the earlier period, resulting in an enhanced eastward transport of Fe. Second, as a
result of stronger tradewinds, the upwelling was deeper and stronger during the upwelling-favorable season
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during the early period, increasing the vertical transport of Fe to the surface. The implications of this nonlinear
response in ocean biogeochemistry for climate change are discussed.
PICES XV
W5-3216
Oral
The establishment of the atmosphere-surface wave-ocean circulation coupled numerical
model and its applications
Zhenya Song and Fangli Qiao
First Institute of Oceanography, State Oceanic Administration, 6 Xianxialin Road, Qingdao, 266061, PR China
E-mail: [email protected]
A common problem of coupled ocean-atmosphere general circulation models (CGCMs) without flux correction
is that the simulated equatorial cold tongue generally tends to be too strong, narrow, and extends too far
westward. This bias in SST simulation is attributed to two causes: coupling flux errors and inaccurate
parameterizations, and numerical inaccuracies. One important reason may be the inaccurate reconstructed
mixed layer and thermocline depth arising from an imperfect vertical mixing scheme.
Based on wave-circulation coupled theory, the MASNUM atmosphere-wave-circulation coupled model was
established. It incorporates the MASNUM wave number spectral model and the coupled ocean-atmosphere
general circulation model, FGCM-0. This model is applied to study climate research. The results compared
with FGCM-0 simulations are summarized as follows:
(1) Compared with the results from the original CGCM (FGCM-0), the modeled SST increases more than 0.8°
with the maximum of 1.2° in the eastern Pacific (160-180ºE, 0-3ºN), while the western boundary of the 26.0°
isotherm moves from 165ºE to 180ºE. The overly-westward extension of the simulated equatorial cold tongue is
suppressed by incorporating wave-induced mixing in the model. The simulated SST is generally improved and
the maximum improvement is more than 1.0°. The simulated SST improvement in the north tropical Pacific is
much better than that in the southern tropical Pacific.
(2) Compared with Levitus data, the error in globally averaged SST decreases to 0.09° from 1.03°. The error in
the tropical region (0-360E, 25N-25S) averaged SST decreases to 0.10° from 1.19°, while the error decreases
from 1.28° to 0.37° in the Indian Ocean, to 0.01° from 1.15° in the tropical Pacific, and to 0.62° from 1.81° in
the tropical Atlantic.
(3) An analysis of the Nino3 Index indicates that the atmosphere-wave-circulation coupled model can better
simulate the main character of ENSO events. The cycle simulated by the established coupled model is 2.5years, which is close to the observed value of 2.8-years, while it is 5-years for the original coupled model. The
difference of the amplitude decreases from 2.412° to 1.035°, and the improvement reaches 27%.
(4) An analysis of the western equatorial Pacific and Indian Ocean sea surface wind shows that the atmospherewave-circulation coupled model can better simulate the warm pool and the Indian Ocean. It also suppresses the
too strong eastern wind by reducing the cold bias of SST.
(5) A process analysis indicates that wave-induced mixing drops the SST in the OGCM because strengthened
vertical mixing can bring more cold water upward, and in the coupled model the non-uniformity of the SST
decreases can generate the horizontal gradient of the SLAP. This leads to the ocean surface circulation anomaly
which can restrain the overly-westward extension of the cold tongue in the tropical Pacific. But most
importantly is that the vertical circulation anomaly induced by the horizontal circulation is the key factor in
suppressing the overly-westward extension of the cold tongue. A net heat flux has a bad effect on the overwestward cold tongue extension.
The MASNUM atmosphere-wave-circulation coupled model established in this paper successfully solves a
common problem, namely that the simulated equatorial cold tongue is generally too strong, narrow, and extends
too far westward. The model can also simulate ENSO and climate better. It is important for climate research
and the development of the climate system coupled model.
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PICES XV
W5-2874
Oral
Evaluation of climatic variability in the Far-Eastern Seas using regional data sets
Elena I. Ustinova
Pacific Research Fisheries Centre (TINRO-Centre), 4 Shevchenko Alley, Vladivostok, 690950, Russia. E-mail: [email protected]
The purpose of the study is to evaluate the low-frequency variability of some climatically significant parameters
in the Far-Eastern Seas using regional data sets based on historical observations. Multi-year data on ice cover,
air and water temperature from the meteorological stations located along the coast of the Far-Eastern Seas are
the longest time series of relatively regular and homogeneous hydrometeorological information for the Seas,
although still the total observation number is small. Ice cover data are based mainly on regular aircraft
observations carried out by Russian Hydrometeorological Service before 1992 and on satellite information after
that. The longest time series of ice cover was the data on the maximum annual ice cover from 1929 to 2006 for
the Okhotsk Sea. It is noted, that since 1996 extreme ice cover in the Okhotsk Sea has been observed more
often. Large-scale changes in the ice cover of the Sea are connected to variations of globally-averaged surface
air temperature anomalies for time scales longer than 7 years. The main difference in the spectra of air
temperature at the meteorological stations and ice cover is that the air temperature variance is mainly comprised
of quasi-biennial oscillations, while the major part of the ice cover variance is comprised of low-frequency
oscillations with periods about a decade and more. There are seasonal distinctions in the low-frequency
variability of water and air temperature.
PICES XV
W5-3047
Oral
What will the North Pacific look like in the next 40 years?
Muyin Wang1, James E. Overland2 and Nicholas A. Bond1
1
2
JSIAO, University of Washington, 7600 SandPoint Way NE, Bldg. 3, Seattle, WA, 98115, U.S.A.
Pacific Marine Environmental Laboratory, NOAA, 7600 Sand Point Way NE, Seattle, WA, 98115-6349, U.S.A.
Projections for the North Pacific from 16 coupled ocean-atmospheric models obtained as part of the 4th IPCC
Assessment show a future climate with a basin-wide warming signal that will surpass the amplitude of the
Pacific Decadal Oscillation (PDO) - the leading mode of natural climate variability - in a few decades, even for
the modest CO2 increase scenarios (SA1B and B1). The models were first evaluated against observed variations
in the late 20th century. All models reproduce the PDO as the dominant mode in the Pacific in 20 th century, with
11 models producing a spatial correlation with the observed pattern greater than 0.6. There will be substantial
changes on not just the basin-scale, but also regional processes such as sea-ice concentration in the Bering Sea,
shifts in ocean fronts, ocean circulation in the NW Pacific and coastal upwelling off of the US west coast. Of
particular importance is that the spatial pattern of the model-projected temperature trends is more uniform than
the east-west dipole pattern of the PDO. Prior relationships between climate and ecosystems, especially those
associated with the PDO, may not be robust long into the 21st century.
PICES XV
W5-3003
Oral
Characteristics of Pacific sea surface temperature variability associated with global
warming during the 20th century
Sang-Wook Yeh, Cheol-Ho Kim, Young-Gyu Park and Hong-Sik Min
Ocean Climate and Environment Research Division, Korea Ocean Research and Development Institute, Ansan, P.O. Box 29, Seoul, 425600, Republic of Korea. E-mail: [email protected]
Observations of the Earth’s near-surface temperature since 1900 show that a global-mean temperature increase
occurs from 1910 to 1940 and from 1970 to the present (Tett et al., 1999, Nature), and these increases
correspond with the variability of global sea surface temperature (SST). Previous studies have suggested that
though the primary cause of global warming during the first half of the 20th may be due to variations in the sun’s
irradiance, during the late 20th it is mainly due to human induced anthropogenic forcing. In this paper we
analyze the characteristics of Pacific SST variability during these two epochs. In particular, we focus on the
differences of North Pacific SST variability in terms of its amplitude, period and connections with the tropics.
Our result indicates that there are striking differences in linear trends in the North Pacific, supporting the
hypothesis that the causes of SST increase during the two epochs are quite different.
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