scholarly journals The timescale and extent of thermal expansion of the global ocean due to climate change

Ocean Science ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 179-184 ◽  
Author(s):  
S. Marčelja
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Temperature Variation ◽  
Sea Level ◽  
Heat Content ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
The Past ◽  
Surface Temperatures

Abstract. With recently improved instrumental accuracy, the change in the heat content of the oceans and the corresponding contribution to the change of the sea level can be determined from in situ measurements of temperature variation with depth. Nevertheless, it would be favourable if the same changes could be evaluated from just the sea surface temperatures because the past record could then be reconstructed and future scenarios explored. Using a single column model we show that the average change in the heat content of the oceans and the corresponding contribution to a global change in the sea level can be evaluated from the past sea surface temperatures. The calculation is based on the time-dependent diffusion equation with the known fixed average upwelling velocity and eddy diffusivity, as determined from the steady-state limit. In this limit, the model reduces to the 1966 Munk profile of the potential temperature variation as a function of depth. There are no adjustable parameters in the calculation and the results are in good agreement with the estimates obtained from the in situ data. The method allows us to obtain relevant timescales and average temperature profiles. The evaluation of the thermosteric sea level change is extended back to the beginning of accurate sea surface temperature records. The changes in sea surface temperature from 1880 until the present time are estimated to have produced a thermosteric sea level rise of 35 mm. Application to future IPCC scenarios gives results similar to the average prediction of more complex climate models.

scholarly journals The timescale and extent of thermal expansion of the oceans due to climate change

2009 ◽  
Vol 6 (3) ◽  
pp. 2975-2992
Author(s):  
S. Marčelja
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Temperature Variation ◽  
Sea Level ◽  
Heat Content ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
The Past ◽  
Surface Temperatures

Abstract. With recently improved instrumental accuracy, the change in the heat content of the oceans and the corresponding contribution to the change of the sea level can be determined from in situ measurements of temperature variation with depth. Nevertheless, it would be favourable if the same changes could be evaluated from just the sea surface temperatures because the record could then be extended into the past and projected into the future. We show here that the average change in the heat content of the oceans and the corresponding contribution to a change in the sea level can be evaluated from the past sea surface temperatures. The calculation is based on the time-dependent diffusion equation with constant upwelling velocity and has no adjustable parameters. In the steady-state limit it recovers the well-known profile of the potential temperature variation as a function of depth. The results are in good agreement with the estimates obtained from the in situ data, even though most of the warming occurs in the upper 1000 m. The method allows us to obtain relevant timescales and average temperature profiles. The evaluation of the thermosteric sea level change is extended back to the beginning of accurate sea surface temperature records in 1880. The changes in sea surface temperature from 1880 until the present time led to a thermosteric sea level rise of 3 cm and to a commitment for a future rise of 5 cm.

scholarly journals Influence of Upwelling in the Southern Waters of Java on CO2 Concentration in Kototabang, Agam District West

2020 ◽  
Vol 5 (1) ◽  
pp. 8
Author(s):  
Martono Martono ◽  
Fanny Aditya Putri
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Chlorophyll A ◽  
Descriptive Analysis ◽  
Co2 Concentration ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
Chlorophyll A Concentration ◽  
Surface Temperatures

<p>Absorption of atmospheric CO<sub>2</sub> by the sea through two processes, namely solubility pumps and biological pumps. This study aims to determine the effect of upwelling in the southern waters of Java on atmospheric CO<sub>2</sub> concentrations in Kototabang. The data used are in situ CO<sub>2</sub> concentration, sea surface temperature and chlorophyll-a concentration from 2004-2016. The method used was descriptive analysis. The results showed that upwelling that occurred during JJA-SON caused a decrease in sea surface temperature to 26.8 °C and 27.1 °C respectively, as well as an increase chlorophyll-a concentration to 2.03 mg/m<sup>3</sup> and 2.19 mg/m<sup>3</sup>. In both seasons CO<sub>2</sub> concentration in Kototabang dropped to 385.8 ppm and 385.4 ppm. Meanwhile, when there was no upwelling during DJF-MAM, sea surface temperatures rose to 28.8 °C and 29.0 °C, and chlorophyll-a concentration dropped to 0.32 mg/m<sup>3</sup> and 0.54 mg/m<sup>3</sup>. CO<sub>2</sub> concentration in DJF and MAM increased to 386.3 ppm and 386.5 ppm. Based on these results it is known that when upwelling occurs, CO<sub>2</sub> concentration decrease and vice versa.</p>

scholarly journals A spatiotemporal reconstruction of sea-surface temperatures in the North Atlantic during Dansgaard–Oeschger events 5–8

2018 ◽  
Vol 14 (6) ◽  
pp. 901-922 ◽  
Author(s):  
Mari F. Jensen ◽  
Aleksi Nummelin ◽  
Søren B. Nielsen ◽  
Henrik Sadatzki ◽  
Evangeline Sessford ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
North Atlantic ◽  
General Circulation ◽  
Sea Surface ◽  
Reconstruction Method ◽  
Sea Surface Temperatures ◽  
Proxy Data ◽  
Surface Temperatures ◽  
Temperature Reconstructions

Abstract. Here, we establish a spatiotemporal evolution of the sea-surface temperatures in the North Atlantic over Dansgaard–Oeschger (DO) events 5–8 (approximately 30–40 kyr) using the proxy surrogate reconstruction method. Proxy data suggest a large variability in North Atlantic sea-surface temperatures during the DO events of the last glacial period. However, proxy data availability is limited and cannot provide a full spatial picture of the oceanic changes. Therefore, we combine fully coupled, general circulation model simulations with planktic foraminifera based sea-surface temperature reconstructions to obtain a broader spatial picture of the ocean state during DO events 5–8. The resulting spatial sea-surface temperature patterns agree over a number of different general circulation models and simulations. We find that sea-surface temperature variability over the DO events is characterized by colder conditions in the subpolar North Atlantic during stadials than during interstadials, and the variability is linked to changes in the Atlantic Meridional Overturning circulation and in the sea-ice cover. Forced simulations are needed to capture the strength of the temperature variability and to reconstruct the variability in other climatic records not directly linked to the sea-surface temperature reconstructions. This is the first time the proxy surrogate reconstruction method has been applied to oceanic variability during MIS3. Our results remain robust, even when age uncertainties of proxy data, the number of available temperature reconstructions, and different climate models are considered. However, we also highlight shortcomings of the methodology that should be addressed in future implementations.

Cooling and freshening of the eastern equatorial Pacific over the last 2000 years

2020 ◽  
Author(s):  
Gerald Rustic ◽  
Athanasios Koutavas ◽  
Thomas Marchitto
Keyword(s):  
Stable Isotope ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Eastern Pacific ◽  
Ice Age ◽  
Sea Surface Temperatures ◽  
Surface Temperatures ◽  
Eastern Equatorial Pacific

&lt;p&gt;Sea surface temperatures in the eastern equatorial Pacific exert powerful influence on the climate beyond the tropics through strong atmosphere-ocean coupling. Records of eastern Pacific sea surface temperatures are of vital importance for identifying the linkages between short-term climate variability and long-term climate trends. Here we reconstruct eastern equatorial Pacific sea surface temperature and salinity from paired trace metal and stable isotope analyses in foraminifera from a sediment core near the Gal&amp;#225;pagos Islands. Sea surface temperatures are correlated with reconstructed Northern and Southern hemisphere temperature records suggesting a common origin. We propose that this temperature signal originates in the extra-tropics and is transmitted to the eastern Pacific surface via its source waters. We find exceptions to this cooling during the Little Ice Age and during the last century, where notable sea surface temperature increases are observed. We calculate &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;sw&amp;#160;&lt;/sub&gt;from paired stable isotope and trace element analyses and derive salinity, which reveals a significant trend toward fresher surface waters in the eastern equatorial Pacific. The overall trend toward cooler and fresher sea surface conditions is consistent with longer-term trends from both the Eastern and Western Pacific.&lt;/p&gt;

scholarly journals A spatio-temporal reconstruction of sea-surface temperatures in the North Atlantic during Dansgaard-Oeschger events 5&ndash;8

2017 ◽  
pp. 1-36
Author(s):  
Mari F. Jensen ◽  
Aleksi Nummelin ◽  
Søren B. Nielsen ◽  
Henrik Sadatzki ◽  
Evangeline Sessford ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
North Atlantic ◽  
General Circulation ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
Proxy Data ◽  
The North ◽  
Surface Temperatures ◽  
Temperature Reconstructions

Here we establish a spatio-temporal evolution of the sea-surface temperatures in the North Atlantic over Dansgaard Oeschger (DO) events 5&amp;ndash;8 (c. 30&amp;ndash;40 ka) using the proxy surrogate reconstruction method. Proxy data suggest a large variability in North Atlantic sea-surface temperatures during the DO-events of the last glacial period. However, proxy data availability is limited and cannot provide a full spatial picture of the oceanic changes. Therefore, we combine fully coupled, general circulation model simulations with planktic foraminifera based sea-surface temperature reconstructions to obtain a broader spatial picture of the ocean state during DO-events 5&amp;ndash;8. The resulting spatial sea-surface temperature patterns agree over a number of different general circulation models and simulations. We find that sea-surface temperature variability over the DO-events is characterized by colder conditions in the subpolar North Atlantic during stadials than during interstadials, and the variability is linked to changes in the Atlantic Meridional Overturning circulation, and in the sea-ice cover. Forced simulations are needed to capture the strength of the temperature variability and to reconstruct the variability in other climatic records not directly linked to the sea-surface temperature reconstructions. Our results are robust to uncertainties in the age models of the proxy data, the number of available temperature reconstructions, and over a range of climate models.

scholarly journals Studi Pendahuluan Variasi Suhu Permukaan Laut dan Sebaran Aerosol di Laut Sawu

2021 ◽  
Vol 1 (2) ◽  
pp. 9-15
Author(s):  
Ashari Wicaksono ◽  
Nike Ika Nuzula
Keyword(s):  
Numerical Model ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Low Temperatures ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
Surface Temperatures ◽  
Aerosol Distribution ◽  
Preliminary Study

Research related to aerosols in Indonesia is still very minimal compared to sea surface temperature parameters and other oceanographic parameters. This study is a preliminary study that aims to determine the variation in aerosol distribution and its influence by variations in sea surface temperatures in the areas crossed by Arlindo, especially the savu sea. Savu sea surrounded by Flores islands (Sumba Regency, Kupang Regency, and Manggarai Regency) has a variation of SPL from 22 - 30 °C, where in the wetar strait, ombai strait, and sumba strait in the northwest part of sawu often occur low temperatures. While the value of aerosol spread is ranging from 0 - 0.3. Thus, a numerical model is needed that can help in analyzing the results that currently exist.

scholarly journals Linkages between Arctic and Mid-Latitude Weather and Climate: Unraveling the Impact of Changing Sea Ice and Sea Surface Temperatures

2021 ◽  
Author(s):  
Ralf Jaiser ◽  
Mirseid Akperov ◽  
Alexander Timazhev ◽  
Erik Romanowsky ◽  
Dörthe Handorf ◽  
...  
Keyword(s):  
Sea Ice ◽  
Boundary Conditions ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Polar Vortex ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
Temperature Changes ◽  
Surface Temperatures ◽  
The Impact

&lt;p&gt;&lt;span&gt;The study addresses the question, if Arctic sea ice decline is the main driver of observed changes in terms of Arctic-midlatitude linkages during winter. We discuss, if the increase of global sea surface temperatures plays an additional role. A set of four model sensitivity experiments with different sea ice and sea surface temperature boundary conditions is analyzed and compared to observed changes in reanalysis data. A detection of atmospheric circulation regimes is performed. These regimes are evaluated for their cyclone and blocking characteristics and their changes in frequency during winter to reveal tropospheric changes induced by the change of boundary conditions. Furthermore, the impacts on the large-scale circulation up into the stratosphere are investigated. The results show that the impact from sea surface temperature changes is generally stronger than the impact of sea ice concentration changes alone. However, in particular in terms of the startospheric pathway, the combined impact of sea ice and sea surface temperature changes reproduces findings from the reanalysis best.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;For early winter, the observed increase in atmospheric blocking in the region between Scandinavia and the Ural are primarily induced by the changes in sea surface temperatures. Nevertheless, the impacts on the stratospheric circulation in terms of a weakened polar vortex, are only observed if sea ice is reduced and sea surface temperatures are increased. Late winter impacts are more inconsistent in the model sensitivity study, but slightly improved when both components of forcing are changed. In this context, we further identify a discrepancy in the model to reproduce the weakening of the stratospheric polar vortex through blocking induced upward propagation of planetary waves.&lt;/span&gt;&lt;/p&gt;

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