impact of global warming on tropical cyclones and ...

Open Access e-Journal Earth Science India- www.earthscienceindia.info Popular Issue, 9 (I), January, 2016, p. 1-19

IMPACT OF GLOBAL WARMING ON TROPICAL CYCLONES AND VULNERABILITY OF MAN-MADE ISLANDS IN THE ARABIAN GULF Arun Kumar During the past two hundred years, tropical cyclones have caused deaths of about 1.9 million people worldwide. Tropical cyclones interrupt infrastructure causing power outages, collapse of bridges and destruction of roads…………… A changing climate leads to changes in the frequency, intensity, spatial extent, duration, and timing of extreme weather and climate events, and can result in unprecedented extreme weather and climate events. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen…….. It is very likely that the number of cold days and nights has decreased and the number of warm days and nights has increased on a global scale……………. Several new townships are being developed in the Arabian Gulf on reclaimed land along the coastal regions. United Arab Emirates (UAE), Qatar and Bahrain are spending huge sums of money on such mega urban development projects.

This article presents a brief overview of the current descriptions on widely used terms such as climate change, global warming and a few other related words. These terms are defined and explained according to the documents published by the United Nations Inter-governmental Panel on Climate Change (IPCC, 2012). A brief discussion about tropical cyclones and how global warming impacts them is provided. Few countries in the Arabian Gulf region are building man-made islands for infrastructure development and economic gain severely impacting the coastal ecosystem and destroying marine life (Figure 1). This article throws light on the potential future danger to such islands considering the history of tropical cyclones that have impacted the Arabian Peninsula in the past and could potentially strike in the future with higher frequency and ferocity due to increasing global warming. It is suggested that the construction of man-made islands in the Arabian Gulf are not in the best interest of either the economy or the environment of the region. Tropical cyclones are a major atmospheric hazard that could potentially cause immense damage or even the total destruction of these man-made islands. The seriousness of the climate change issue and urgency to do everything possible to mitigate it was highlighted in the following newspaper report (Dawn, November 30, 2015). According to an Associated Press (AP) dispatch from COP-21, Paris (November, 2015),“since the last binding agreement to fight global warming in Kyoto, Japan, in 1997, the planet Earth now has become hotter, waterier, and wilder. Now world leaders gather for COP-21 in Paris to try to do more, as it is clear that the global environment has changed dramatically over the past 18 years leading to trillions of tons of melting ice, a rise in sea level of a couple of inches. Epic weather disasters, including killer heat waves and monster storms, have plagued Earth.” “At the time of Kyoto, if someone talked about climate change, they were talking about something that was abstract in the future”, said Marcia McNutt, the former US Geological 1


Survey director who was picked to run the National Academies of Sciences. “Now, we’re talking about changing climate, something that’s happening now. You can point to event after event that is happening in the here and now that is a direct result of changing climate.” “Since 1997 the West Antarctic and Greenland ice sheets have lost 5.5 trillion tons of ice, or 5 trillion metric tons”, according to Andrew Shepherd at the University of Leeds, who used NASA and European satellite data. The five-year average surface global temperature for January to October has risen by nearly two-thirds of a degree Fahrenheit, or 0.36 degrees Celsius, between 1993-97 and 2011-15, according to the US National Oceanic and Atmospheric Administration (NOAA). In 1997, Earth set a record for the hottest year, but it didn’t last. Records were set in 1998, 2005, 2010 and 2014, and it is sure to happen again in 2015 when the results are in from the year, according to NOAA. With 1.2 billion more people in the world, carbon dioxide emissions from the burning of fossil fuels climbed nearly 50 per cent between 1997 and 2013, according to the US Department of Energy. The world is spewing more than 100 million tons of carbon dioxide a day now. The five deadliest heat waves of the past century — in Europe in 2003, Russia in 2010, India and Pakistan this year, Western Europe in 2006 and southern Asia in 1998 — have come in the past 18 years, according to the International Disaster Database run by the Centre for Research on the Epidemiology of Disaster in Belgium.

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Tropical Cyclones Tropical cyclones are giant rotating tropical storms with winds of at least 119 km per hour; the most powerful cyclones have wind velocities greater than 250 km per hour. They are called hurricanes in the Atlantic, typhoons in the Pacific, and cyclones in the Indian Ocean (Raven and Berg, 2001). Tropical cyclones begin as tropical depressions (strong tropical storms resulting from a high-altitude trough of low pressure) that are formed very close to the Equator where they gather the most energy from heated ocean water. As the tropical storms increase in size, their low-pressure core pulls more and more air into the system. As the surface wind speed hits a sustained velocity of 119 km per hour or higher, the tropical storm becomes a mature tropical cyclone (Demillo, 1994). A more technical definition of the tropical storm is provided by the National Weather Service of the United States Government (Strager, 2013); according to them tropical cyclone is defined as “A warm-core, non-frontal synoptic-scale cyclone, originating over tropical or subtropical waters with organized deep convection and a closed surface wind circulation about a well-defined center.” They typically form over relatively warm water oceans and derive their energy through the evaporation of water from the ocean surface, which ultimately condenses into clouds and rain when moist air rises and cools to saturation. The strong rotating winds of a tropical cyclone are a result of the conservation of angular momentum imparted by the Earth's rotation as air flows inwards toward the axis of rotation (Figure 2). As a result, they rarely form within 5° of the Equator.Tropical cyclones are typically between 100 and 2,000 km in diameter, and they produce strong winds and rain, generate high waves, damaging storm surges, and tornadoes, but typically weaken rapidly over land where they are cut off from their primary energy source. Thus coastal regions are damaged most from a tropical cyclone. These cyclones carry heat energy away from the tropical zone towards the temperate zone playing an important role in modulating regional and global climate (https://en.wikipedia.org/wiki/Tropical_cyclone). During the past two hundred years, tropical cyclones have caused deaths of about 1.9 million people worldwide. Tropical cyclones interrupt infrastructure causing power outages, collapse of bridges and destruction of roads. Tropical storms bring salt water from the oceans causing many coastal freshwater ecosystems to become saline resulting in mortality of some plant and animal species.Tropical cyclones are beneficial for the dry regions where they bring much-needed rains. They also help maintain the global heat balance by moving warm, moist tropical air to the middle latitudes, and regulate the thermohaline circulation through upwelling (https://en.wikipedia.org/wiki/Tropical_cyclone).

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Climate Change Climate Change is a change in the state of the climate that can be identified by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcing, or to persistent anthropogenic changes in the composition of the atmosphere or in land use. Both extreme weather events and extreme climate events are referred to collectively as ‘climate extremes.’ A changing climate leads to changes in the frequency, intensity, spatial extent, duration, and timing of extreme weather and climate events, and can result in unprecedented extreme weather and climate events. Many extreme weather and climate events continue to be the result of natural climate variability. Natural variability will be an important factor in shaping future extremes in addition to the effect of anthropogenic changes in climate (IPCC 2012). Exposure and vulnerability are key determinants of disaster risk and of impacts when risk is realized. For example, a tropical cyclone can have very different impacts depending on where and when it makes landfall. A changing climate leads to changes in the frequency, intensity, spatial extent, duration, and timing of extreme weather and climate events, and can result in unprecedented extreme weather and climate events. There is low confidence in any observed long-term (i.e., 40 years or more) increases in tropical cyclone activity (i.e., intensity, frequency, duration), after accounting for past changes in observing capabilities (IPCC 2012).

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Impact of Global Warming on Tropical Cyclones Earth’s average temperature is based on daily measurements recorded at land-based meteorological stations around the world as well as data from weather balloons, orbiting satellites, transoceanic ships, and sea-surface buoys with temperature sensors (Raven and Berg, 2001). According to the National Oceanic and Atmospheric Administration (NOAA), global temperatures in 1998 may have been highest in the last 1200 years; and the last two decades of the 20th century were its warmest. As a result during the past few decades the sea level has risen slightly, glaciers worldwide have retreated, and extreme weather events have occurred with increasing frequency in certain regions. There is a strong consensus among the climate scientists that the 21st century will experience significant climate change and that human activities will have been at least partly responsible for this change. United Nations Inter-governmental Panel on Climate Change (IPCC) provides scientific statements on climate change (Raven and Berg, 2001). Few experts think that we can not yet detect any increase in frequency or intensity of tropical cyclones (https://en.wikipedia.org/wiki/North_Indian_Ocean_tropical_cyclone).

El Niño's impacts on weather patterns El Niño events are anomalous warming of ocean surface waters in the eastern tropical Pacific, generally brought on by the suppression of upwelling off the coasts of Equador and Northern Peru, and along the Equator east of the International Date Line. El Niño conditions typically last for 12 to 18 months and occur every three to seven years. El Niño is accompanied by weather extremes in various parts of the world. La Niña events are episodes of strong winds and resulting strong upwelling and usually low sea-surface temperatures in the central and eastern areas of the tropical Pacific. These episodes are linked to particular sets of climate conditions elsewhere around the Earth. La Niña is essentially the opposite of El Niño. El NiñoSouthern Oscillation (ENSO) is the term for the coupled ocean-atmosphere interaction in tropical Pacific characterized by episodes of anomalously high sea-surface temperatures in the equatorial and tropical eastern Pacific. It is associated with large swings in surface air pressure between the eastern and western tropical Pacific and is the most prominent source of inter-annual variability in weather and climate around the world (King et al. 2007). During an El Niño event, the physical relationships between wind patterns, ocean currents, oceanic and atmospheric temperature, and biosphere break down into destructive forces.Their impacts are felt all over the world, where the disruption of normal local weather patterns can have tragic and/or profound economic consequences. As warm water migrates eastward, increased heat and moisture rises into the atmosphere, altering the weather patterns in neighboring regions, which in turn can ripple out to affect other region weather patterns around the globe. El Niño can also cause severe droughts over Australia, Indonesia, and parts of southern Asia. While El Niño is known to lower the probability of hurricanes in the Atlantic, it increases the chances of cyclones and typhoons in the Pacific. The 1982-83 El Niño is estimated 5


by NOAA to have caused some $8 billion in damages due to floods, severe storms, droughts and fires around the world (Herring, 1999 inhttp://earthobservatory.nasa.gov/Features/ElNino/). 21st Conference of the Parties (COP-21), Paris Recently the IPCC participated in the 21 st Conference of the Parties (COP-21) to the United Nations Framework Convention on Climate Change (UNFCCC) and related events in Paris, between November 30 and December 12, 2015 (http://ipcc.ch). Some of the following information regarding global warming is being reproduced here with minor changes from the Synthesis Report website (http://ar5-syr.ipcc.ch/). Observed Changes and their Causes: Human influence on the climate system is clear. Recent anthropogenic emissions of greenhouse gases are the highest in history. Recent climate changes have had widespread impacts on human and natural systems. Observed changes in the climate system: Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen. Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850. The period from 1983 to 2012 was likely the warmest 30-year period of the last 1400 years in the Northern Hemisphere, where such assessment is possible. Causes of climate change: Anthropogenic greenhouse gas (GHG) emissions since the preindustrial era have driven large increases in the atmospheric concentrations of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Between 1750 and 2011, cumulative anthropogenic CO2 emissions to the atmosphere were 2040 ± 310 GtCO2. About 40% of these emissions have remained in the atmosphere (880 ± 35 GtCO2); the rest were removed from the atmosphere and stored on land (in plants and soils) and in the ocean. The ocean has absorbed about 30% of the emitted anthropogenic CO2, causing ocean acidification. About half of the anthropogenic CO2 emissions between 1750 and 2011 have occurred in the last 40 years. Anthropogenic greenhouse gas emissions have increased since the pre-industrial era, driven largely by economic and population growth, and are now higher than ever. This has led to atmospheric concentrations of carbon dioxide, methane and nitrous oxide that are unprecedented in at least the last 800,000 years. Their effects, together with those of other anthropogenic drivers, have been detected throughout the climate system and are extremely likely to have been the dominant cause of the observed warming since the mid-20th century. Concentration of Chlorofluorocarbons (CFCs) like Chlorofluorocarbons-12 and Chlorofluorocarbons-11 also cause global warming because all the gases absorb infrared radiation or heat in the atmosphere, which ultimately slows the natural heat flow into space, warming the lower atmosphere. Some of the lower atmosphere heat is transferred to the oceans causing them to warm as well. Although this retention of heat in the atmosphere is the reason for the sustenance of a wide variety of life on Earth, the continued warming of atmosphere would be 6


detrimental to their survival. Since these gases trap the sun’s radiation like glass does in a glass house, the natural trapping of heat in the atmosphere is referred to as the Greenhouse effect; and the gases that absorb infrared radiation are known as greenhouse gases (Raven and Berg, 2001). Impacts of climate change: In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans. Impacts are due to observed climate change, irrespective of its cause, indicating the sensitivity of natural and human systems to changing climate. Evidence of observed climate change impacts is strongest and most comprehensive for natural systems. In many regions, changing precipitation or melting snow and ice are altering hydrological systems, affecting water resources in terms of quantity and quality. Many terrestrial, freshwater and marine species have shifted their geographic ranges, seasonal activities, migration patterns, abundances and species interactions in response to ongoing climate change. Assessment of many studies covering a wide range of regions and crops shows that negative impacts of climate change on crop yields have been more common than positive impacts. Extreme events: Changes in many extreme weather and climate events have been observed since about 1950. Some of these changes have been linked to human influences, including a decrease in cold temperature extremes, an increase in warm temperature extremes, an increase in extreme high sea levels and an increase in the number of heavy precipitation events in a number of regions. It is very likely that the number of cold days and nights has decreased and the number of warm days and nights has increased on a global scale. It is likely that the frequency of heat waves has increased in large parts of Europe, Asia and Australia. It is very likely that human influence has contributed to the observed global scale changes in the frequency and intensity of daily temperature extremes since the mid-20th century. It is likely that human influence has more than doubled the probability of occurrence of heat waves in some locations. There are likely more land regions where the number of heavy precipitation events has increased than where it has decreased. Recent detection of increasing trends in extreme precipitation and discharge in some catchments implies greater risks of flooding at aregional scale. It is likely that extreme sea levels (for example, as experienced in storm surges) have increased since 1970, being mainly a result of the rising mean sea level. Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability. Future Climate Changes, Risks and Impacts: Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems. Limiting climate change would require substantial and sustained reductions in greenhouse gas emissions which, together with adaptation, can limit climate change risks. 7


Future risks and impacts caused by a changing climate: Climate change will amplify existing risks and create new risks for natural and human systems. Risks are unevenly distributed and are generally greater for disadvantaged people and communities in countries at all levels of development. Risk of climate-related impacts results from the interaction of climate-related hazards (including hazardous events and trends) with the vulnerability and exposure of human and natural systems, including their ability to adapt. Rising rates and magnitudes of warming and other changes in the climate system, accompanied by ocean acidification, increase the risk of severe, pervasive and in some cases irreversible detrimental impacts. Some risks are particularly relevant for individual regions, while others are global. The overall risks of future climate change impacts can be reduced by limiting the rate and magnitude of climate change, including ocean acidification. Climate change beyond 2100, irreversibility and abrupt changes: Many aspects of climate change and associated impacts will continue for centuries, even if anthropogenic emissions of greenhouse gases are stopped. The risks of abrupt or irreversible changes increase as the magnitude of the warming increases. Tropical Cyclones in the Arabian Sea Following information is primarily based on the information from website https://en.wikipedia.org/wiki/North_Indian_Ocean_tropical_cyclone. In the Indian Ocean north of the Equator, tropical cyclones can form throughout the year. The Arabian Seais in the northwest of the Indian Ocean and its coast is shared byIndia, Yemen, Oman, Iran, Pakistan, Sri Lanka, Maldives and Somalia. The Arabian Sea is responsible for the yearly cycling of its waters through monsoons. During summer, strong winds blow from the southwest to the northeast, bringing rain to the Indian subcontinent, and during winter, the winds are milder and blow in the opposite direction, from the northeast to the southwest. Tropical cyclones in this sea are abbreviated ARB by the India Meteorological Department (IMD), the official Regional Specialized Meteorological Centre (RSMC) of the Arabian Sea. Although cyclones are supposedlyrare events in the Arabian Sea during the recent past strong tropical cyclones have occurred and hit hard the Arabian Peninsula, for example, super cyclonic storm Gonu was the strongest recorded tropical cyclone of the Arabian Sea (Tyagi et al. 2011). The systematic studies of tropical systems in the Arabian Sea were initiated in the 19th century by Henry Piddington. Between 1839 and 1858, he used meteorological logs from vessels that navigated the seas and published them in the Journal of the Asiatic Society of Bengal. During the 2004 post monsoon season the IMD started to name tropical cyclones (https://en.wikipedia.org/wiki/North_Indian_Ocean_tropical_cyclone). Tropical cyclones are frequently generated in the Indian Ocean and the Arabian Sea but not all impact the Arabian Peninsula. In May/June 1885, a very strong Aden cyclone was formed off the west of southern India and moved northwest towards Socotra Island and Yemen coast.The German corvette Augusta, the French dispatch boat Renard, and the British ship SS Speke Hall were all lost in this storm in the Gulf of Aden. The cyclone continued westward and eventually dissipated as it 8


moved into the entrance of the Red Sea, crossing the coast of Djibouti(https://en.wikipedia.org/wiki/Pre1980_North_Indian_Ocean_cyclone_seasons#June_18 85_Aden_cyclone). The following are the wettest tropical cyclones that hit (https://en.wikipedia.org/wiki/List_of_wettest_tropical_cyclones_by_country#Oman). S. N. Rain (mm) 1 610.0

Duration (Hours) 24.02

Name Gonu Cyclone

Year 2007

2

488.0

19.21

Phet Cyclone

2010

3

482.4

18.99

Masirah Cyclone

1977

4

300.2

11.82

T.S. 02A Cyclone

1996

5

285.5

11.24

Muscat Cyclone

1890

6

251.0

9.882

Oman Cyclone

2002

7

250.0

9.843

Ashobaa Cyclone

2015

8

230.0

9.055

Salalah Cyclone

1963

9

82.0

3.23

Salalah Cyclone

1959

Oman

The following tropical cyclones hit the Arabian Peninsula in recent years.

Cyclone Gonu (Figure 3) Kumar (2013) gave the following details about the cyclone Gonu.“It is generally believed that the countries of Arabian Peninsula appear to be ‘safe’ from the devastation of tropical storms generated in the Arabian Sea. However, the tropical cyclone Gonu (Figure 5) proved that such severe events do occur in the Arabian Sea and can also be devastating. On June 5, 2007 the intensity of cyclone Gonu had reached a Category 5, with sustained winds measuring 160 miles per hour(http://www.nasa.gov/vision/earth/lookingatearth/gonu.html)”. According to the Joint Typhoon Warning Center (http://earthobservatory.nasa.gov/ NaturalHazards/natural_hazards_v2.php3?img_id=14328) it was the most powerful cyclone ever to threaten the Arabian Peninsula since record keeping began in 1945. This cyclone had weakened by the time it hit Oman’s capital Muscat. It still caused enormous damage to the city’s infrastructure and loss of life and property.” Tyagi et al. (2011) published a detailed report on this cyclone and considered it to be the most powerful cyclone to hit the Arabian Peninsula in recorded history.

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Cyclone Phet (Figure 4) This cyclone was active during May 31 to June 6, 2010 and was a very severe cyclonic storm of category 4. At its peak wind velocity of 90 miles per hour impacted Omani coast of the Arabian Peninsula on June 4 and later Pakistan on June 6. Actually three cyclonic storms were generated in 2010, two in the Arabian Sea and one in the Bay of Bengal, and only cyclone Phet had hit the Arabian Peninsula; their details were provided by Kumar (2013) as follows.

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“In 2010, three cyclonic storms were generated in North Indian Ocean Cyclone Season, first cyclone Laila was generated in the Bay of Bengal and had a land fall along the Andhra Pradesh on the east coast of India. This caused heavy loss of life and property. Second cyclone Bandu was active during May 19-23 in the Arabian Sea with 50 mph wind velocity. According to Wikipedia (http://en.wikipedia.org/wiki/Cyclone_Phet) this cyclone impacted the coast of Somalia and the Yemeni island ‘Abed Alkorey’ in the Gulf of Aden. It caused the death of a girl and destruction of many houses in the island. On May 20 the storm disabled a cargo vessel, MV Dubai Moon, and left it drifting off the Somali coast where 23 crew members were rescued by helicopters from the Royal Navy frigate HMS Chatham. The cargo ship later sank. The third tropical cyclone named Phet (Figure 6) was active during May 31 to June 6, was very severe cyclonic storm of category 4 at its peak intensity with 90 mph wind impacted Oman on June 4 and Pakistan on June 6. It left 44 people dead and loss of property worth 780 million dollars.” An extremely rare atmospheric event occurred in this region when two tropical cyclones hit the Arabian Peninsula within a week; they were Cyclone Chapala (October 31, 2015) and Cyclone Megh (November 7, 2015).

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Cyclone Chapala (Figure 5) This was a rare tropical cyclone with winds of more than 100 kilometers per hour that made landfall in southeastern Yemen on October 31, 2015 causing heavy flooding and enormous damage. It was brewed in the Arabian Sea, and wreaked havoc on the island of Socotra, located 350km off the coast of Yemen. In Socotra three people were killed, more than 200 injured, and dozens of houses and hamlets were severely damaged or washed away. Streets of Mukalla, the provincial capital of Hadramawt, were heavily flooded with 40 inches of water, and seafront roads were badly damaged by high waves. It brought maximum sustained winds of 130 kilometers per hour with gusts of up to 145 kilometers per hour when it made landfall. (http://www.aljazeera.com/news/2015/11/deadly-yemen-cyclone-triggers-heavy-flooding151103142058157.html). This cyclone killed eight people on the Yemeni mainland and more than 18,000 people (almost a third of Socotra's population) were displaced and 237 homes were completely destroyed (http://www.bbc.com/news/world-middle-east-34764971).

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Chapala had dumped 16 to 24 inches of rain over the island of Socotra, and according to NASA it was equivalent to nearly a decade of rainfall. Over18,000people, more than a third of Socotra’s population, were displaced by Chapala(https://www.washingtonpost.com/news/capitalweather-gang/wp/2015/11/09/unprecedented-second-freak-tropical-cyclone-to-strike-yemen-inthe-same-week/). Cyclone Chapala unloaded at least a year’s worth of rain in a single day in affected areas. River beds that were previously dry were swollen. Empty lakes were filled and coastal zones are inundated with water miles inland (https://www.washingtonpost.com/news/capital-weather-gang/wp/2015/11/05/before-and-aftercyclone-chapalas-devastating-rains-in-yemen-interactive-slider/).

Cyclone Megh (Figure 6) This was the second extremely rare and powerful) cyclone to hit Yemen's Socotra Island within one week on November 7, 2015. Two people died as cyclonic winds up to 167 kilometers per hour coupled with torrential rainsdevastated the island with flash floods.The storm also damaged reefs, eroded soil and uprooted many rare plants including dragon's blood trees (Figure 10) endemic to Socotra. Megh was several times worse than Chapala because it passed directly over the Socotra Island resulting in material damage worse than before, as a larger number of homes were destroyed and 5,000 more people got displaced.Almost 230,000 people on mainland Yemen were exposed to high winds and heavy rainfall. Tropical cyclones supposedly are rare over the Arabian Peninsula but two cyclones within one was an extraordinary event (http://www.bbc.com/news/world-middle-east-34764971). Historical records of cyclones in the region date back to 1891 andtwo tropical cyclones never struck Yemen in the same year, much less in the same week. On Saturday, Megh reached an intensity equivalent to a Category 3 cyclone and hit Socotra which was still reeling from Chapala which had caused 11 deaths.Cyclone Chapala was really bad in Socotra, but Megh was “several times worse”, according to the Socotra Environment Office. Megh became the first tropical cyclone on record to reach Category 3 intensity during the month of November. Ocean temperatures one to two degrees Celsius warmer than normal helped fuel these cyclones. Sea surface temperatures in the Arabian Sea are at an all-time high. According to Eric Blake, a forecaster at National Hurricane Center, present Arabian Sea temperature is 0.6 degree Celsius warmer than 1997. Blake said a combination of factors, including El Niño and climate warming, contributed to the ocean’s record-shattering warmth. Like cyclone Chapala, flash flooding near the coast was the most significant hazard from cyclone Megh (https://www.washingtonpost.com/news/capital-weathergang/wp/2015/11/09/unprecedented-second-freak-tropical-cyclone-to-strike-yemen-in-the-sameweek/).

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Man-Made Islands in the Arabian Gulf In an earlier article I described the man-made islands in the Arabian Gulf as follows (Kumar, 2009): “Several new townships are being developed in the Arabian Gulf on reclaimed land along the coastal regions (Figure 1). United Arab Emirates (UAE), Qatar and Bahrain are spending huge sums of money on such mega urban development projects. Saudi Arabia used reclamation to expand the size of Tarut Island for urban development. The city of Dubai (Figure 7) is at the forefront of such development where five giant new offshore island communities are being developed (http://en.wikipedia.org/wiki/Palm_Islandsand http://www.nakheel.com). They are ‘The Palm Jebel Ali’, ‘The Palm Jumeirah’, ‘The Palm Deira’, ‘The World’ and ‘The Universe’. ‘The Pearl Qatar’ (Figure 8) is a similar type of a mega project being developed by Qatar on reclaimed land (http://www.thepearlqatar.com/main.aspx). The Kingdom of Bahrain too is developing a similar urban development project (http://www.durratbahrain.com) on reclaimed land (Figure 9). These islands have been designed and are under construction for the maximum possible length of coastlines so that a large number of beachside luxury homes could be built. Townships are being constructed on these islands for thousands of luxury homes with sea-side views. They will include tens of thousands of homes,

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apartments, hotels, marinas, golf courses, and other types of commercial and recreational complexes, etc. Such projects in Qatar and Bahrain include high rise apartment complexes also.”

According to the website (http://www.traveladvisortips.com/top-10- interesting-palmisland-dubai-facts/) “The planning of the Palm Island Dubai consisted of over one hundred studies just to determine the feasibility of the project.” An internet search for the feasibility studies (http://www.nakheel.com/en/communities/palm-jumeirah/) provided the following information, “Palm Jumeirah, Nakheel’s flagship project, is the world’s largest man-made island and is comprised of a two kilometre long trunk, a crown made up of 17 fronds and a surrounding crescent.” It further stated, “Following a number of years of feasibility studies, the Palm Jumeirah was launched in 2001, with reclamation starting in the same year. From the end of 2006, the island's first residences – comprising 4,000 luxury villas and apartments were handed over during a phased period. Since then, the tourism, leisure and retail elements of the island have been developed, creating a spectacular, world-renowned residential and tourism destination.” The environmental and engineering justification for the construction of these palm islands is as follows: “The Palm Island, as it is seen today, is the outcome of immense planning, and more than one hundred feasibility studies were carried out to review several major aspects of the project, such as marina design, transportation, civil engineering and technology. Moreover, several veteran divers were roped into examine the rock formations beneath the water and ensure its 15


stability. A specialty of crescent that bounds the island is that it serves as a breakwater and is made using a blend of sand, rocks and geo textile fiber. With more than 300 opening on its each side, the breakwater has the capability to resist harsh weather conditions, especially high waves in the event of storm or typhoon”(http://blog.raynatours.com/10-facts-palm-dubai/).

But there seems to be an admission that constructing such islands will adversely impact the environment and the attempt to protect them in case of high waves generated by storms. Another website (http://dubaiislands.net/dubai-islands-construction.html) while describing the construction of these palm islands admits as follows, “It is not easy to construct eco-friendly artificial islands, especially when we are aware of the wide range of environmental impacts that can be triggered off due to a developmental project of this nature. Dubai Island construction project involved several years of planning and development. Modern techniques were involved, which were carried out by using huge imported machinery.” It is clear that developers of these islands are aware of the environmental issues related to construction of these islands but theyeither seem to ignore the long term geological and atmospheric hazards to these islands or may be not even aware of them (Kumar, 2009, 2013).

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“The crescent that surrounds the Palm Island acts as a breakwater to protect the island from high waves in case of a typhoon or storms. The breakwater consists of sand, geotextile fiber as well as small and medium rocks which help to make it strong and stable. Most of this sand came from the ocean floor so they were able to use natural resources that were already in use.” (http://www.traveladvisortips.com/top-10-interesting-palm-island-dubai-facts/). How much protection these islands will get from the crescent surrounding them will only be demonstrated in case they face a strong cyclonic storm in future, which in my opinion can’t be ruled out. We have several examples from the world about storm related disasters, for example, hurricane Katrina in the USA (http://www.livescience.com/22522-hurricane-katrina-facts.html) and even closer to Dubai, the disaster caused by tropical cyclone Gonu in 2007 is described as follows(https://en.wikipedia.org/wiki/Cyclone_Gonu):“Strong winds knocked out power and telephone lines across the eastern region of the country, leaving thousands isolated until the lines were repaired hours later. The cyclone caused extensive damage along the coastline, including in the city of Sur and the village of Ras al Hadd at the easternmost point of the Omani mainland. In Muscat, winds reached 100 km/h (62 mph), leaving the capital city without power. Strong waves and heavy rainfall flooded streets and some buildings. Police workers in the city sent text messages to keep people away from flooded streets to prevent electrocutions. Little damage was reported to the oil fields of the nation. The liquefied natural gas terminal in Sur, which handles 10 million tonnes of gas each year, was badly hit by the storm and could not be operated. Overall, the cyclone killed 50 people in the country; by the fourth day after it struck the country,

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27 people had been reported missing. Around 20,000 people were affected, and damage in the country was estimated at around $4.2 billion (2007 USD).”

Discussion A wide range of issues related to global warming have been discussed by the Inter Governmental Panel on Climate Change (IPCC) (http://www.ipcc.ch) and various other scientific and environmental organizations all over the world. This issue is of vital importance because it could lead to far reaching socioeconomic and political changes in the world and potentially has disastrous consequences for all life forms on Earth. Environmental impact of global warming on new man-made offshore island communities should be understood in terms of possible changes on the coastal environments. As a result of global warming sea-levels are expected to rise which would seriously impact coastlines and infrastructure development in the coastal environments. Although tropical cyclones affecting the Arabian Peninsula and the Gulf are not common they are becoming more frequent due to the effect of global warming. These can be severe and hazardous as demonstrated by cyclone Gonu in June 2007.

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Murty and El-Sabh (1984) consider that tropical cyclones generated in the Indian Ocean rarely impact the Arabian Gulf or the Arabian Peninsula; they state (p. 667), “The important point made here is that only rarely, if at all the tropical cyclones from the Arabian Sea travel towards the Gulf of Oman and the Arabian Gulf.” But recent observations on the movement of tropical cyclones Gonu (Figure 5; June 5, 2006) and Phet (Figure 6; June 5, 2010) and a few others observed during the past few years cast doubts on this view. Higher frequency and intensity of tropical cyclones in the Arabian Sea may be due to the impact of global warming or a certain cyclic meteorological phenomenon which is when the frequency of Indian Ocean tropical cyclones increasingly move northward impacting the Arabian Gulf and the Arabian Peninsula. In case such tropical storms continue to impact the Arabian region, there is every possibility that future cyclones may impact offshore island communities developed in the Arabian Gulf especially several Palm Islands off Dubai. This is evident from the fact that Cyclone Phet moved further north than Cyclone Gonu closer to the Palm Islands (Kumar, 2013). Acknowledgements: I thank my son Anshuman Kumar for linguistic improvements to this article.

References DAWN November 30, 2015, Earth is warmer and wilder since last climate deal. Demillo, R. 1994. How weather works. ZD Press, Emeryville, California.232 p. IPCC, 2012: Summary for Policymakers. In: Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation [Field, C.B., V. Barros, T.F. Stocker, D. Qin, D.J. Dokken, K.L. Ebi, M.D. Mastrandrea, K.J. Mach, G.-K. Plattner, S.K. Allen, M. Tignor, and P.M. Midgley (eds.)]. A Special Report of Working Groups I and II of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK, and New York, NY, USA, pp. 1-19. King, M. D., Parkinson, C. L., Partington, K. C., and Williams, R. G. 2007.Our changing planet.The view from space.Cambridge Univ. Press.389 p. Kumar, A. 2009. Reclaimed islands and new offshore townships in the Arabian Gulf: potential natural hazards. Current Science, 96(4): 480-485. Kumar, A. 2013. Chapter 12: Natural hazards of the Arabian Peninsula; their causes and possible remediation. Earth System Processes and Disaster Management (Eds. Rajiv Sinha and Rasik Ravindra), pp. 155-180. SpringerSociety of Earth Science Series. Murty, T. S. and El-Sabh, M. I. (1984). Cyclones and storm surges in the Arabian Sea: A brief review. Deep Sea Research, v. 31, pp. 665-670. Raven, P.H. and Berg, L. R. 2001. Environment.3rd Edition.Harcourt College Publishers.602 p. Strager, C. S. 2013. Tropical Cyclone definitions. National Weather Service Instruction 10-604, June 6, 2013. 12 p. (http://www.nws.noaa.gov/directives) Tyagi, A., Bandhopadhyay, B. K., Mohapatra, M., Goel, S., Kumar, N., Mazumdar, A. B. and Khole, M. 2011. A Report on the Super Cyclonic Storm “GONU” during 1-7 June, 2007. Government of India Meteorology Department, IMD MET Monograph: Cyclone Warning Division No. 08/2011, 82 p.

About the Author Dr. Arun Kumar is an Adjunct Professor, Department of Earth Science, Carleton University Ottawa-Carleton Geoscience Centre. 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada Email: [email protected]

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