Many scientists now believe that restriction of CO2 production will not happen in time for the earth to avoid reaching the tipping point when we can no longer stop the release of CO2 and methane from the thawing permafrost and other sources, nor can we stop the melt of sea ice and snow cover with its high albedo reflecting solar radiation back into space. 2018 had the greatest release of CO2 gas into the atmosphere of any year ever.
The tipping point has been forecast for 2030 when CO2 production will no longer be controllable.
This leave us with only geoengineering available to halt the total greenhouse gases that are increasing and thus threatening a worsening global warming.
There are many geoengineering projects conceived including many Solar Radiation Management (SRM) projects. One way to reduce greenhouse gases is to lower the earth’s temperature and water vapor content is lowered when the temperature is lowered, it precipitates out. Water vapor content depends on atmospheric temperatures and are not normally thought of as controllable but Geoengineering can lower temperatures and the average water vapor level. Water vapor is much stronger than CO2 in the atmosphere . Perhaps by a factor of 4.5 .
Ocean Supplied artificial Desert Lakes (OSaDL)
We can achieve significant net negative heat flux if we are able to achieve cooling through first evaporation of large masses of water then the radiation of the latent heat of condensation of much of that mass into the clear night sky. This can be done in select hot-dry sites from newly created inland lakes fed by sea water and where a portion of that water will precipitate as dew, fog, or soil absorption in the nearby desert.
We are recommending urgent research of various SRM projects to reflect more heat back into space and address the heat footprint as well as the carbon footprint. That is what many geoengineering projects do.
Side Benefits Possible from Evaporative Cooling Lakes
There are some wonderful side benefits to the projects whose primary function is evaporative cooling of the air.
- Hydroelectric power generation has long been recognized for the Qattara depression with a drop to the 60 m below sea level. Similar sites with large drops available will also yield hydroelectric power.
- There can be tourism, sailing and water skiing and wind surfing and even hang-gliding from the cliffs of the Qattara depression down to the water level.
- Desalination is possible where large drops in height of the water exist as the pressure can be used for osmotic desalination although some pumping may also be necessary. Thus providing drinking water and irrigation water.
- Some crops such as saltbush grow well in saline soils and saltbush is great at sequestering carbon as the roots will plunge down 60 feet seeking water in desert areas. There are other fodder crops with similar abilities to grow in saline soil. Cropping or harvesting would not remove the roots.
- Pellets can be made from the salt bush plants with 40% protein and so make a great substitute for soy beans in pig food. Some varieties are used for human consumption and are somewhat like spinach
- Fish would be naturally stocked into the lakes as the sea water flowed in. The fishing grounds would only be productive in deep lakes as the evaporation would gradually make it too saline except near the inflow areas and surface areas where salinity would be below the Lake average.
- Local cooling is forecast to be 8 °C ! This cooling will aid new irrigation areas by reducing their rate of evaporation and the amount of desalinated water needed.
- Ground cover will increase near the lakes as the evaporated water will condense at night on the desert sands.
- Employment will be stimulated by the construction projects, then the farming opportunities then the tourists.
- Food scarcity will be reduced by the farms and the sites to use are mostly in counties with low incomes
Other Geoengineering Projects
Geoengineering projects in general should have appeal to even fossil fuel producers as they are an alternative to the short term reduction in CO2 production which looks impossible.
Bill Gates has funded research at Harvard University to plan and cost a “SPACE UMBRELLA”. This calls for the introduction of large quantities of reflective particles into the upper atmosphere to reflect part of the sunlight hitting the earth. Thus cooling the earth. Thank goodness for concerned brilliant billionaires!
Despite any resistance we may need this solution as wild fires (bush fires) are increasing in ferocity, area, range and geographical diversity, from California to Australia to Siberia and we appear to be accelerating towards the tipping point and the UN date of 2030 for the tipping point may be optimistic. We may have even less time to take corrective geoengineering action.
This geoengineering project does however have political hurdles to overcome, one forecast is that China will be drier and India wetter. Our desert lakes project although perhaps slower to activate will however be politically acceptable in most countries due to the associated benefits locally and the offsetting effects internationally.
This geoengineering project and many others are concerned with the heat footprint and its reduction. Lowering the temperature will lower the capacity of the air to hold water vapor which is an even bigger greenhouse gas than CO2. .“It’s true that water vapor is the largest contributor to the Earth’s greenhouse effect. On average, it probably accounts for about 60% of the warming effect. However, water vapor does not control the Earth’s temperature, but is instead controlled by the temperature.” American Chemical Society
Hausfather (2008) rates water vapor as contributing 66 to 85% of global warming and CO2 as contributing 9 to 26%. The average ratio is 76/17 or 4.5 times the effect of CO2 for water vapor.
If we accept this then it becomes imperative to concern ourselves with the heat footprint of our activities as well as our carbon footprint. This directs us towards geoengineering solutions. Quass (2017)
Ming et al ((2014) outline multitudes of geoengineering projects, many of which can yield low cost electric generation and/or also cause heat transfer from the earth to outer space. These include:
Space mirrors, sulfate aerosols, cloud whitening, other albedo boosting projects, solar radiation management, targeting high and cold cirrus clouds, thermal bridging, solar updraft chimneys, super chimneys, artificial tornadoes, polar chimneys and many more.
Hausfather, Z. (2008). The Water Vapor Feedback. Yale Climate Connections. Retrieved from https://www.yaleclimateconnections.org/2008/02/common-climate-misconceptions-the-water-vapor-feedback-2/.
Quass M. F, Quass, J.,Rickels W. Boucher O.(2017) Are there reasons against open-ended research into solar radiation management? A model of intergenerational decision –making under uncertainty. Journal of Environmental Economics and Management 84 (2017) pp 1-17.
Ming T, de Richter R, Liu W, Calliol S (2014) Fighting global warming by climate engineering: Is the Earth radiation management and the solar radiation management any option for fighting climate change? Renewable and Sustainable Energy Reviews 31(2014) pp 792-834.