Decadal predictability of tropical Indo-Pacific Ocean temperature trends due to anthropogenic forcing in a coupled climate model

Abstract Variability of subtropical cell (STC) overturning in the upper Pacific Ocean is examined in a coupled climate model in light of large observed changes in STC transport. In a 1000-yr control run, modeled STC variations are smaller than observed, but correlate in a similar way with low-frequency ENSO-like variability. In model runs that include anthropogenically forced climate change, STC pycnocline transports decrease progressively under the influence of global warming, attaining reductions of 8% by 2000 and 46% by 2100. Although the former reduction is insufficient to fully account for the apparent observed decline in STC transport over recent decades, it does suggest that global warming may have contributed to the observed changes. Analysis of coupled model results shows that STC transports play a significant role in modulating tropical Pacific Ocean heat content, and that such changes are dominated by anomalous currents advecting mean temperature, rather than by advection of temperature anomalies by mean currents.

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Reconciling disparate twentieth-century Indo-Pacific ocean temperature trends in the instrumental record

Nature Climate Change ◽

10.1038/nclimate1591 ◽

2012 ◽

Vol 2 (9) ◽

pp. 691-699 ◽

Cited By ~ 115

Author(s):

Amy Solomon ◽

Matthew Newman

Keyword(s):

Twentieth Century ◽

Pacific Ocean ◽

Ocean Temperature ◽

Temperature Trends ◽

Instrumental Record

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A realistic Greenland ice sheet and surrounding glaciers and ice caps melting in a coupled climate model

Climate Dynamics ◽

10.1007/s00382-021-05816-7 ◽

2021 ◽

Author(s):

Marion Devilliers ◽

Didier Swingedouw ◽

Juliette Mignot ◽

Julie Deshayes ◽

Gilles Garric ◽

...

Keyword(s):

Climate Model ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Coupled Climate Model ◽

Ice Caps

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Is the World Ocean Warming? Upper-Ocean Temperature Trends: 1950–2000

Journal of Physical Oceanography ◽

10.1175/jpo3005.1 ◽

2007 ◽

Vol 37 (2) ◽

pp. 174-187 ◽

Cited By ~ 46

Author(s):

D. E. Harrison ◽

Mark Carson

Keyword(s):

Vertical Structure ◽

World Ocean ◽

Time Variability ◽

Upper Ocean ◽

Ocean Temperature ◽

Similar Magnitude ◽

Subsurface Temperature ◽

Temperature Trends ◽

Uncertainty Estimates ◽

The World

Abstract Subsurface temperature trends in the better-sampled parts of the World Ocean are reported. Where there are sufficient observations for this analysis, there is large spatial variability of 51-yr trends in the upper ocean, with some regions showing cooling in excess of 3°C, and others warming of similar magnitude. Some 95% of the ocean area analyzed has both cooled and warmed over 20-yr subsets of this period. There is much space and time variability of 20-yr running trend estimates, indicating that trends over a decade or two may not be representative of longer-term trends. Results are based on sorting individual observations in World Ocean Database 2001 into 1° × 1° and 2° × 2° bins. Only bins with at least five observations per decade for four of the five decades since 1950 are used. Much of the World Ocean cannot be examined from this perspective. The 51-yr trends significant at the 90% level are given particular attention. Results are presented for depths of 100, 300, and 500 m. The patterns of the 90% significant trends are spatially coherent on scales resolved by the bin size. The vertical structure of the trends is coherent in some regions, but changes sign between the analysis depths in a number of others. It is suggested that additional attention should be given to uncertainty estimates for basin average and World Ocean average thermal trends.

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Effects of Ocean Biology on the Penetrative Radiation in a Coupled Climate Model

Journal of Climate ◽

10.1175/jcli3828.1 ◽

2006 ◽

Vol 19 (16) ◽

pp. 3973-3987 ◽

Cited By ~ 100

Author(s):

Patrick Wetzel ◽

Ernst Maier-Reimer ◽

Michael Botzet ◽

Johann Jungclaus ◽

Noel Keenlyside ◽

...

Keyword(s):

Seasonal Cycle ◽

Marine Biology ◽

Climate Model ◽

Global Climate ◽

Ocean Model ◽

Equatorial Pacific ◽

Shortwave Radiation ◽

Upper Ocean ◽

Biogeochemical Model ◽

Coupled Climate Model

Abstract The influence of phytoplankton on the seasonal cycle and the mean global climate is investigated in a fully coupled climate model. The control experiment uses a fixed attenuation depth for shortwave radiation, while the attenuation depth in the experiment with biology is derived from phytoplankton concentrations simulated with a marine biogeochemical model coupled online to the ocean model. Some of the changes in the upper ocean are similar to the results from previous studies that did not use interactive atmospheres, for example, amplification of the seasonal cycle; warming in upwelling regions, such as the equatorial Pacific and the Arabian Sea; and reduction in sea ice cover in the high latitudes. In addition, positive feedbacks within the climate system cause a global shift of the seasonal cycle. The onset of spring is about 2 weeks earlier, which results in a more realistic representation of the seasons. Feedback mechanisms, such as increased wind stress and changes in the shortwave radiation, lead to significant warming in the midlatitudes in summer and to seasonal modifications of the overall warming in the equatorial Pacific. Temperature changes also occur over land where they are sometimes even larger than over the ocean. In the equatorial Pacific, the strength of interannual SST variability is reduced by about 10%–15% and phase locking to the annual cycle is improved. The ENSO spectral peak is broader than in the experiment without biology and the dominant ENSO period is increased to around 5 yr. Also the skewness of ENSO variability is slightly improved. All of these changes lead to the conclusion that the influence of marine biology on the radiative budget of the upper ocean should be considered in detailed simulations of the earth’s climate.

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Polar amplification in a coupled climate model with locked albedo

Climate Dynamics ◽

10.1007/s00382-009-0535-6 ◽

2009 ◽

Vol 33 (5) ◽

pp. 629-643 ◽

Cited By ~ 183

Author(s):

Rune Grand Graversen ◽

Minghuai Wang

Keyword(s):

Climate Model ◽

Coupled Climate Model ◽

Polar Amplification

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An Assessment of Observed and Simulated Temperature Variability in Sierra de Guadarrama (Spain)

10.5194/egusphere-egu21-6358 ◽

2021 ◽

Author(s):

Cristina Vegas Cañas ◽

J. Fidel González Rouco ◽

Jorge Navarro Montesinos ◽

Elena García Bustamante ◽

Etor E. Lucio Eceiza ◽

...

Keyword(s):

Western Europe ◽

Climate Model ◽

Regional Climate ◽

Monitoring Network ◽

Horizontal Resolution ◽

Temperature Variability ◽

Added Value ◽

Seasonal Temperature ◽

Temperature Trends ◽

Highly Correlated

This work provides a first assessment of temperature variability from interannual to multidecadal timescales in Sierra de Guadarrama, located in central Spain, from observations and regional climate model (RCM) simulations. Observational data are provided by the Guadarrama Monitoring Network (GuMNet; www.ucm.es/gumnet) at higher altitudes, up to 2225 masl, and by the Spanish Meteorological Agency (AEMet) at lower sites. An experiment at high horizontal resolution of 1 km using the Weather Research and Forecasting (WRF) RCM, feeding from ERA Interim inputs, is used. Through model-data comparison, it is shown that the simulations are annually and seasonally highly representative of the observations, although there is a tendency in the model to underestimate observational temperatures, mostly at high altitudes. Results show that WRF provides an added value in relation to the reanalysis, with improved correlation and error metrics relative to observations.The analysis of temperature trends shows a warming in the area during the last 20 years, very significant in autumn. When spanning the analysis to the whole observational period, back to the beginning of the 20th century at some sites, significant annual and seasonal temperature increases of 1&#8451;/decade develop, most of them happening during de 1970s, although not as intense as during the last 20 years.The temporal variability of temperature anomalies in the Sierra de Guadarrama is highly correlated with the temperatures in the interior of the Iberian Peninsula. This relationship can be extended broadly over south-western Europe.

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