In the Middle East and North Africa region, the Arabian Sea plays a major part in both South Asian and African monsoons, providing a source of moisture. Temperature and vapor pressure in the northern Arabian Sea have been steadily increasing since the 1980s and regional sea surface temperatures have seen a steady rise since 2003. Combined, these phenomena are a recipe for disaster.
The warmer average air mass above the sea has an increased capacity to hold water and will take longer to saturate as a result. This lengthens the average time between precipitation events, but is also more likely to produce catastrophically high precipitation when it does.
What can be done to adapt to this new reality? Can infrastructure be adapted, optimized, or possibly even re-imagined to take advantage of such events?
Infrastructure for the capture, transport, and treatment of surface water will need to adapt to the new realities of climate change, in MENA perhaps quicker than anywhere else. Correlation between historically extreme events and the “new normal” could serve to guide the retrofitting of pre-existing infrastructure as well as updated requirements for the construction of new infrastructure. This should be based on sound statistics and up-to-date flood frequency analysis.
If it is determined, for example, that floods that previously qualified as a “500-year event” are now a “100-year event,” then catchment areas, spillway designs, and dam heights should be adjusted to reflect this new reality.
Beyond exposed impoundments and flood control structures, innovative solutions for storage, conveyance, and treatment of water harvested from these extreme events should be considered if the intended end use is municipal or industrial.
Since large swaths of the MENA countries within the Arabian Sea zone are sparsely populated, adaptations that emphasize efficiency and flexibility in capture or conveyance across vast, often arid regions would be essential.
These might include groundwater infiltration basins located in regions statistically determined to be visited by cyclones with increased frequency, covered tanks (to reduce evaporative losses), and pipelines from these areas to strategic transfer points in regional infrastructure. Incorporating passive treatment of captured water, solar, or even small-scale hydroelectric generation into these designs can augment water and power security.
Source type is also important. Smaller countries or those with more homogenous landscapes (such as Bahrain or Qatar) only need to focus on adaptations to the particular type of extreme event they most often experience. Infrastructure in Arabian Sea zone countries with diverse geography such as Oman, however, may be adapted to capitalize on episodic heavy rainfall or, more rarely, heavy snowfall events and the differences in timing of arrival of water from each.
Monsoon rains are highly localized, and some of the countries that border the Arabian Sea, like Oman, are uniquely positioned to take advantage not just of “Khareef season” but of its reversal as well.
Between the months of June and September, the Salalah region in southern Oman will experience rain from the prevailing south west relies that set up along the southern coast as warm, moist air from the Arabian Sea sweeps toward the Indian Subcontinent.
Toward the end of the Northern Hemisphere summer, this pattern reverses as East Africa heats up, driving winds from the Gulf of Oman to drop rain and, sometimes, snow on the Hajar Mountains.
By contrast, cyclones may affect large areas, and are an increasingly common occurrence in the Arabian Sea, bringing significant rainfall, storm surge, and high winds. With the aid of advanced sitting tools (a combination of geographical information system, artificial intelligence, or updated global circulation models, for example) key regions of the landscape could be engineered or enhanced to take advantage of such events by acting as large-scale catchment facilities, capturing precious runoff, wave energy, or controlling sediment transport. Maximizing the local use of such resources — for small-scale power, landscape irrigation, or environmental flows — would remove the need for both conveyance and treatment.
If it sounds as though the line between landscape and infrastructure has blurred, perhaps it should. If buildings and roadways are engineered to withstand the impacts of “extreme” climatic events, why not re-imagine the environment to dovetail with adapted power and water supply infrastructure and take advantage of the potential windfall? Hurricane Harvey dumped more than 20x1012 gallons of water on the US Gulf Coast in the summer of 2017. Had the storm stalled over the US Southwest, 17 years of drought would have been undone and surface system reservoirs would have been filled within the space of one week.
The blueprint for transforming events such as these from liability into potential windfall already exists, albeit on a smaller scale. Many city and regional-level utilities outside MENA incentivize simultaneous compliance with safety and environmental standards prior to approving new infrastructure. Scaling up such an approach would require a similar leap up in planning and regulatory perspective. Urban planning would become regional planning, with the coordination between civil, geotechnical, and environmental engineering taken to new levels.
Funding options for such projects would need to evolve alongside the rising threats posed by climate change. Options for build-operate-own scenarios under public-private partnerships could be negotiated through non-governmental, UN, or World Bank-affiliated organizations, such as the Green Climate Fund or the Global Adaptation Fund, if government funding for affected countries in the MENA region were limited. Rates for water could be structured according to the ephemeral nature of the resource.
The degree of difficulty with which the resource is captured and conveyed could be incorporated, with the associated costs wrapped into current operations and management. The money saved by not having to pump and treat an equivalent volume of this “free water” could be used to further stretch the resource by being funneled back into reuse-recycling programs, for example.
The details of such programs are, at this stage, less important than a broader array of strategies for taking advantage of potential opportunities to mitigate the damage caused by climate change.
Rather than planning for climate conditions just based on the status quo of risk management, consider that, if the scale and robustness of infrastructure are being tested at a level never before experienced in modern times due to the amplification of climate change impacts, perhaps it is time for a similar quantum leap of thought on how we approach these challenges by viewing these climate risks as opportunities.
The MENA countries within the climate influence of the Arabian Sea will certainly need to buffer against the adverse impacts of extreme weather but may also look toward finding innovative benefits from experiencing this level of climate vulnerability.
Courtesy: Middle East Institute
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