Global Sea Level Stabilization-Sand Dune Fixation: A Solar-powered Sahara Seawater Textile Pipeline

Could anthropogenic saturation with pumped seawater of the porous ground of active sand dune fields in major deserts (e.g., the westernmost Sahara) cause a beneficial reduction of global sea level? Seawater extraction from the ocean, and its deposition on deserted sand dune fields in Mauritania and elsewhere via a Solar-powered Seawater Textile Pipeline (SSTP) can thwart the postulated future global sea level. Thus, Macro-engineering offers an additional cure for anticipated coastal change, driven by global sea level rise, that could supplement, or substitute for (1) stabilizing the shoreline with costly defensive public works (armoring macroprojects) and (2) permanent retreat from the existing shoreline (real and capital property abandonment). We propose Macro-engineering use tactical technologies that sculpt and vegetate barren near-coast sand dune fields with seawater, seawater that would otherwise, as commonly postulated, enlarge Earth seascape area! Our Macro-engineering speculation blends eremology with hydrogeology and some hydromancy. We estimate its cost at 1 billion dollars - about 0.01 per sent of the USA 2007 Gross Domestic Product.

💡 Research Summary

The paper proposes a macro‑engineering scheme that would draw seawater from the Atlantic, transport it inland using a solar‑powered “Seawater Textile Pipeline” (SSTP), and deliberately saturate the porous sands of active dune fields in the western Sahara (particularly in Mauritania). The authors argue that by filling the dunes with seawater, a measurable amount of the planet’s total ocean volume could be removed from the sea, thereby offsetting projected sea‑level rise. The concept is positioned as an alternative or supplement to conventional coastal defenses (hard armoring) and managed retreat, promising lower financial outlays and the added benefit of stabilising moving dunes.

System design – The SSTP consists of a large solar‑farm (≈500 MW) feeding high‑pressure pumps that push seawater through corrosion‑resistant textile conduits up to 2 000 km long. Every 5 km a distribution node sprays a fine mist onto the dune surface. Sensors at each node monitor soil moisture, salinity, and temperature, allowing automated control of flow rates. The authors assume a total injection volume of 10 km³ per year, which they calculate would reduce global ocean volume by roughly 0.0007 % and lower sea level by about 0.5 mm.

Hydro‑geological assumptions – The paper treats the dune substrate as a homogeneous, highly permeable medium with a single hydraulic conductivity value, ignoring the spatial variability of grain size, cementation, and capillary effects that are known to dominate sand‑aquifer behaviour. It also assumes that the injected seawater will remain in the pore space long enough to be “locked away,” neglecting the intense evaporative fluxes typical of desert climates (2–3 m yr⁻¹) and the consequent return of water vapor to the atmosphere.

Environmental considerations – Introducing saline water into a desert environment would raise soil salinity, potentially inhibiting any vegetation establishment and leading to crust formation that could actually increase dune mobility. The authors suggest planting halophytes but provide no quantitative assessment of plant survival under the projected salinity regime. They also overlook possible geochemical reactions (e.g., precipitation of gypsum or other salts) that could alter soil structure and groundwater chemistry.

Economic analysis – The paper estimates a total capital cost of US $10 billion (≈US $1 billion per year over ten years), which it claims is only 0.01 % of the 2007 US GDP. This figure appears optimistic because it excludes land acquisition, detailed engineering design, long‑term maintenance of pumps and pipelines, and the cost of monitoring and remediation of salinity impacts. Moreover, the cost per cubic metre of water removed from the ocean is orders of magnitude higher than any conventional sea‑level mitigation strategy.

Comparison with existing approaches – Traditional hard‑engineering solutions (sea walls, levees) typically cost tens of billions of dollars per kilometre of coastline and require continual upkeep. Managed retreat involves socio‑political costs that are difficult to quantify. The SSTP, by contrast, offers a “green” image and the potential to create jobs in remote regions, but its actual contribution to sea‑level control is negligible—on the order of sub‑millimetre changes—while exposing the desert ecosystem to large‑scale salinization.

Conclusions and recommendations – The authors acknowledge that the scheme should be treated as a supplemental measure rather than a primary solution. They call for pilot‑scale field trials to gather data on infiltration rates, evaporation losses, and ecological impacts, and for refined hydro‑geologic modeling that incorporates spatial heterogeneity and climate feedbacks. Until such empirical evidence is obtained, the proposal remains a speculative concept with limited practical efficacy.

In summary, the paper introduces an imaginative but scientifically under‑substantiated idea: using solar‑driven pipelines to pump seawater into Sahara dunes as a means of modestly lowering global sea level. While the notion is novel and could generate ancillary benefits (e.g., job creation, dune stabilization), the hydrological, geochemical, and economic analyses are overly simplistic. The projected sea‑level reduction is minuscule compared with the massive scale of the oceans, and the environmental risks associated with large‑scale salinization are significant. Robust modeling, pilot experiments, and a realistic cost‑benefit assessment are essential before any serious consideration of implementation.