Climate Change impact on wave energy in the Persian Gulf
Author
Kamranzad, Bahareh, Etemad-Shahidi, Amir, Chegini, Vahid, Yeganeh-Bakhtiary, Abbas
Published
2015
Journal Title
Ocean Dynamics
Version
Accepted Manuscript (AM)
DOI
https://doi.org/10.1007/s10236-015-0833-y
Copyright Statement
© 2015 Springer Berlin / Heidelberg. This is an electronic version of an article published in
Ocean Dynamics, Volume 65, Issue 6, pp 777-794, 2015. Ocean Dynamics is available online
at: http://link.springer.com/ with the open URL of your article.
Downloaded from
http://hdl.handle.net/10072/167706
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Article title: Climate Change impact on wave energy in the Persian Gulf
Journal name: Ocean Dynamics
Authors:
- Bahareh Kamranzad, PhD, Ocean Engineering and Technology Research Center, Iranian National
Institute for Oceanography and Atmospheric Science, No. 3, Etemadzadeh St., Fatemi Ave., Tehran,
1411813389, IR Iran, Fax: +98-21-66944869
E-mail address: kamranzad@inio.ac.ir
- Amir Etemad-Shahidi
*
, PhD, Griffith School of Engineering, Gold Coast campus
Griffith University QLD 4222, Australia
Tel: +61-07-5552 9267, Fax: +61-07-5552-8065
*
Corresponding Author, E-mail: a.etemadshahidi@griffith.edu.au
-Vahid Chegini, PhD, Ocean Engineering and Technology Research Center, Iranian National Institute
for Oceanography and Atmospheric Science, No. 3, Etemadzadeh St., Fatemi Ave., Tehran,
1411813389, IR Iran, Fax: +98-21-66944869
E-mail address: vahid.chegini@gmail.com
- Abbas Yeganeh-Bakhtiary, PhD, School of Civil Engineering, Iran University of Science and
Technology,
Tehran, Iran, P.O. Box 16765-163
E-mail address: yeganeh@iust.ac.ir
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Abstract
Excessive usage of fossil fuels and high emission of greenhouse gases have increased the earth’s
temperature, and consequently have changed the patterns of natural phenomena such as wind speed,
wave height, etc. Renewable energy resources are ideal alternatives to reduce the negative effects of
increasing greenhouse gases emission and climate change. However, these energy sources are also
sensitive to changing climate. In this study, the effect of climate change on wave energy in the Persian
Gulf is investigated. For this purpose, future wind data obtained from CGCM3.1 model were
downscaled using a hybrid approach and modification factors were computed based on local wind data
(ECMWF) and applied to control and future CGCM3.1 wind data. Downscaled wind data was used to
generate the wave characteristics in the future based on A2, B1 and A1B scenarios, while ECMWF
wind field was used to generate the wave characteristics in the control period. The results of these two
30-yearly wave modelings using SWAN model showed that the average wave power changes slightly
in the future. Assessment of wave power spatial distribution showed that the reduction of the average
wave power is more in middle parts of the Persian Gulf. Investigation of wave power distribution in
two coastal stations (Boushehr and Assalouyeh ports) indicated that the annual wave energy will
decrease in both stations while the wave power distribution for different intervals of significant wave
height and peak period will also change in Assalouyeh according to all scenarios.
Keywords: wave energy; climate change; CGCM3.1; Persian Gulf
1. Introduction
Global observations indicate that the worldwide temperature has increased by about 0.74ºC per century
(Solomon et al., 2007). Satellite measurements show that the extent of snow cover has decreased about
10% since the late 1960s. International Panel on Climate Change (IPCC) also highlighted the changing
precipitation in the middle and high latitudes of the Northern Hemisphere. In addition, the rate of
global mean sea level rise is determined to be 1 to 2 mm/yr during the 20
th
century (Ghosh and Misra,
2010). A rising trend of wave height is also reported in North East Atlantic since the late 1980s, which
is estimated to be about 2% per year and around 30 to 50% in thirty years (Carter and Draper, 1988;
Carter and Bacon, 1991). Furthermore, the recent investigations indicate that there is an increase in
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mean sea level, significant wave height and average wind speed to about 30 cm/century, 7 to 10
cm/century and 1 m/s/century, respectively (Sündermann et al., 2001). Factors causing climate change
include ocean processes such as the motion of tectonic plates, variations in solar radiation, variations in
the earth's orbit, changes in greenhouse gas concentrations due to the human activities, etc. Since
greenhouse gases greatly affect the temperature of the earth, increase in their emission cause increase in
earth temperature. Recent studies also show that one of the main effective parameters in global
warming is the increase of the greenhouse gases emission due to the development activities (Houghton
et al., 2001). Indeed, a high level of carbon dioxide produced by excessive use of fossil fuels is the
main reason of global warming (Houghton et al., 2001). Global warming due to the increasing
greenhouse gases emission can affect highly on environment and human activities such as sea level
rise, flooding in coastal areas, erosion of sandy beaches, etc. (Kont et al., 2003).
Renewable energy resources are alternatives for the fossil fuels. These sources of energy are green and
clean and can reduce the negative effects of increasing in greenhouse gases emission and global
warming. Marine renewable energies are valuable energy resources in areas adjacent to the seas or
oceans (e.g. Morim et al., 2014). International Energy Agency (IEA) (IEA-OES, 2007) declared that
the global oceans contain the capacity of 93100 TWh/yr, which is the same or greater than the current
global power generation capacity (17400 TWh/yr) (Tsai et al., 2012). Among the marine renewable
energy resources, waves contain the highest energy density (Leijon et al., 2003). Moreover,
predictability as well as the low visual and environmental impact makes the wave energy a valuable
renewable energy resource (Iglesias et al., 2009). However, the amount of energy captured from the
renewable resources can be influenced by climate change (Breslow and Sailor, 2002; Harrison and
Wallace, 2005). Therefore, it is essential to investigate the effects of climate change on renewable
energy resources. Changes in the wind or wave patterns induced by the climate change can be
evaluated based on the field observations or the climate prediction models. General Circulation Models
or Global Climate Models (GCMs) are developed for simulation of global climate response due to
increasing greenhouse gases emission with different emission scenarios in low resolutions while
Regional Climate Models (RCMs) are developed as local models with higher resolution for considering
the different responses of climate to the rising greenhouse gases’ emission.
There are many studies around the world investigating the effect of climate change on wind or wave
regime using different methods. For example, Chini et al. (2010), using data obtained from a
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continental shelf climatic wave model, showed that the emission scenarios result in an increase of 12%
for extreme wave height for 100-yr return period in eastern coasts of UK. According to studies of
Harrison and Wallace (2005), wind speed has increased about 15 to 20% during four decades. Reeve et
al. (2011) used both global and regional climate models for assessing the impact of climate change on
wave energy in UK and showed that the wave energy will increase by about 2 to 3% according to A1B
scenario and will decrease by about 1 to 3% according to B1 scenario. Pryor et al. (2004) investigated
the temporal and spatial variation in wind speed and power using the data obtained from a GCM, i.e.,
HadCM3 (Stratton, 1999) and local wind fields, i.e., ECMWF (Simmons and Gibson, 2000) and
NCEP/NCAR (Kalnay et al., 1996) in Baltic Sea and indicated that the wind power has no significant
change in the future.
Charles et al. (2012) used the climate model ARPEGE-Climat (Gibelin and Déqué 2003) and showed
that the wave height will decrease in the future about 20 cm in summer in the Bay of Biscay. Lionello
et al. (2003), using downscaled ECHAM-4 model in the Adriatic Sea and found that the extreme wave
height will decrease in the future. In Mediterranean, the results obtained from a regional climate model
showed that the distribution of significant wave height will change seasonally (Lionello et al., 2008).
Segal et al. (2001) used RegCM2 (Giorgi et al., 1993) model and represented that the daily average
wind power will decrease up to 30% in US. Breslow and Sailor (2002) pointed out that the climate
change causes a reduction of 10 to 15% in wind speed and therefore, 30 to 40% for wind power.
Pereira de Lucena et al. (2010) used a regional climate model in Brazil and indicated that the wind
power will not change in the future.
Considering the growth of population and industries around the seas adjacent to Iran, providing the
electricity in future is a very important issue. The marine energies and especially the wave energy are
appropriate candidates for achieving this purpose. Hence, recently, marine renewable energy resources
such as wind and wave power potentials have been widely investigated in Iran for its adjacent seas, i.e.,
Persian Gulf, Gulf of Oman and Caspian Sea. Abbaspour and Rahimi (2011) evaluated the wave
energy potential in some coastal locations in the northern coasts of the Persian Gulf. Assessment of
wave energy distribution in the whole Persian Gulf was carried out by Etemad-Shahidi and Kamranzad
(2011) and Kamranzad et al. (2013a) and the wave energy potential in selected areas was investigated
by Kamranzad et al. (2014). Evaluation of wave energy potential in the northern coasts of the Gulf of
Oman was also carried out by Saket and Etemad-Shahidi (2012). Similarly, Kamranzad et al. (2012),
