Climate change projection of wave climate due to Vardah cyclone in the Bay of Bengal

AbstractExtreme waves will undergo changes in the future when exposed to different climate change scenarios. These changes are evaluated through the analysis of significant wave height (Hs) return values and are also compared with annual mean Hs projections. Hourly time series are analyzed through a seven-member ensemble of wave climate simulations and changes are estimated in Hs for return periods from 5 to 100 years by the end of the century under RCP4.5 and RCP8.5 scenarios. Despite the underlying uncertainty that characterizes extremes, we obtain robust changes in extreme Hs over more than approximately 25% of the ocean surface. The results obtained conclude that increases cover wider areas and are larger in magnitude than decreases for higher return periods. The Southern Ocean is the region where the most robust increase in extreme Hs is projected, showing local increases of over 2 m regardless the analyzed return period under RCP8.5 scenario. On the contrary, the tropical north Pacific shows the most robust decrease in extreme Hs, with local decreases of over 1.5 m. Relevant divergences are found in several ocean regions between the projected behavior of mean and extreme wave conditions. For example, an increase in Hs return values and a decrease in annual mean Hs is found in the SE Indian, NW Atlantic and NE Pacific. Therefore, an extrapolation of the expected change in mean wave conditions to extremes in regions presenting such divergences should be adopted with caution, since it may lead to misinterpretation when used for the design of marine structures or in the evaluation of coastal flooding and erosion.

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The role of the simulation setup in a long-term high-resolution climate change projection for the southern African region

Theoretical and Applied Climatology ◽

10.1007/s00704-011-0420-1 ◽

2011 ◽

Vol 106 (1-2) ◽

pp. 153-169 ◽

Cited By ~ 19

Author(s):

Andreas Haensler ◽

Stefan Hagemann ◽

Daniela Jacob

Keyword(s):

Climate Change ◽

High Resolution ◽

African Region ◽

Climate Change Projection ◽

Southern African Region

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Statistically downscaling climate change projection of precipitation and temperature over the semi-arid Yarmouk Basin, Jordan

International Journal of Global Warming ◽

10.1504/ijgw.2021.10039766 ◽

2021 ◽

Vol 24 (3/4) ◽

pp. 261

Author(s):

Moayyad S. Shawaqfah ◽

Fayez A. Abdulla ◽

Alham W. Al Shurafat

Keyword(s):

Climate Change ◽

Climate Change Projection ◽

Yarmouk Basin ◽

Semi Arid ◽

Precipitation And Temperature

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Statistical Analysis on the Extreme Events of Big Waves Under Wave Climate Change Around Taiwan Waters

Volume 6: Ocean Engineering ◽

10.1115/omae2011-49896 ◽

2011 ◽

Author(s):

Ching-Her Hwang ◽

Wen-Ching Lee ◽

Wen-Fang Hsieh ◽

Ching-Piao Tsai ◽

Hwa Chien

Keyword(s):

Climate Change ◽

Wave Field ◽

Extreme Events ◽

Wind Field ◽

Wave Climate ◽

Model Parameters ◽

Climate Change Research ◽

Weather Bureau ◽

Central Weather Bureau ◽

Typhoon Wind

This study aimed to analyze the statistical characteristics of wave heights, wave energy and wave steepness, in order to investigate the wave climate changes around Taiwan Waters, especially for extreme events of big waves. The operational observation of Taiwan sea waves was initiated by the Central Weather Bureau in 1998; however, due to insufficient data length and low data space coverage, the data are unable to serve as references for long-term wave climate change research. Hence, this study adopted the SWAN (Simulation of Wave in Nearshore) Numerical Wave Hindcasting Method, which is a common method used in many studies, to hindcast the history of a wave field. The re-analysis on wind field data of the last 60 years (1948∼2008), published by the National Centers for Environmental Prediction (NCEP), was employed to make the wind field grid consistent with the hindcast wave field grid. Moreover, the Typhoon Wind Field Grid Down Scaling technique proposed by Winter & Chiou (2007) was applied to interpolate a U10 analysis field that better fits an actual typhoon wind field. The hindcast wave data were compared and validated with directional spectra, which were observed by the meteorological/oceanographic data buoys set up by the Central Weather Bureau and Water Resources Agency since 1997. Longdong, Hualien and Hsinchu Stations were chosen to represent the wave characteristics of sea areas around the island of Taiwan. According to observation data, model parameters were adjusted so that the hindcast results could be closer to observed data in Taiwan sea areas.

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Complex coastlines responding to climate change: do shoreline shapes reflect present forcing or "remember" the distant past?

10.5194/esurf-2016-35 ◽

2016 ◽

Author(s):

Christopher W. Thomas ◽

A. Brad Murray ◽

Andrew D. Ashton ◽

Martin D. Hurst ◽

Andrew K. A. P. Barkwith ◽

...

Keyword(s):

Climate Change ◽

Wave Climate ◽

Quasi Equilibrium ◽

Morphological Response ◽

Antecedent Conditions ◽

Coastline Evolution ◽

Aspect Ratios ◽

Order Of Magnitude ◽

Offshore Wave ◽

Hysteresis Behaviour

Abstract. A range of planform morphologies emerge along sandy coastlines as a function of offshore wave climate. It has been implicitly assumed that the morphological response time is rapid compared to the time scales of wave-climate change, meaning that coastal morphologies simply reflect the extant wave climate. This assumption has been explored by focussing on the response of two distinctive morphological coastlines – flying spits and cuspate cusps – to changing wave climates, using a coastline evolution model. Results indicate that antecedent conditions are important in determining the evolution of morphologies, and that sandy coastlines can demonstrate hysteresis behaviour. In particular, antecedent morphology is particularly important in the evolution of flying spits, with characteristic timescales of morphological adjustment on the order of centuries for large spits. Characteristic timescales vary with the square of aspect ratios of capes and spits; for spits, these timescales are an order of magnitude longer than for capes (centuries vs. decades). When wave climates change more slowly than the relevant characteristic timescales, coastlines are able to adjust in a quasi-equilibrium manner. Our results have important implications for the management of sandy coastlines where decisions may be implicitly and incorrectly based on the assumption that present-day coastlines are in equilibrium with current conditions.

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