A quick search on the absorption of infrared by seawater, see pages 81 and 106 and figs 21 & 22 in the book "The Ocean, their Physics, Chemistry and General Biology" https://publishing.cdlib.org/ucpressebooks/view?docId=kt167nb66r&chunk.id=d3_2_ch04&toc.id=ch04&toc.depth=1&brand=eschol&anchor.id=fig021#X indicates that 99.5% of IR is absorbed in a layer of thickness 5.3cm. Hence, it is hard to see how algae of most types could darken it in the IR spectrum much more than a thin layer of seawater itself does.
Sev Clarke On Sunday, September 16, 2018 at 8:50:07 PM UTC+10, Andrew Lockley wrote: > > Algae doesn't lighten the sea. It darkens it in the IR, which is dominant. > Nadine Mengis and I looked into this; we presented at CEC-14, but didn't > publish. > > Andrew Lockley > > On Sun, 16 Sep 2018, 07:59 Franz Dietrich Oeste, < > [email protected] <javascript:>> wrote: > >> Hi all, >> >> The basis of the MCB method of Salter et al. is sea water. Sea water is a >> salty water with a slightly alkaline pH value above 7. The ISA method >> generated FeCl3 aerosol (ISA) has an acidic pH around 2. >> This are not the only differences of the methods: The ocean surface needs >> an efficient cooling to prevent from hurricane developement. Salter's >> method delivers this cooling *only* by cloud whitening. The ISA method >> use cloud whitening plus several additional cooling methods like sea >> surface whitening/brightening by algae, methane depletion..... According to >> this much more efficient sea surface cooling the ISA method is the better >> hurricane prevention than MCB. >> >> Another article about the physics of hurricanes below. >> >> Best, >> Franz >> >> ------ Originalnachricht ------ >> Von: "Russell Seitz" <[email protected] <javascript:>> >> An: "geoengineering" <[email protected] <javascript:>> >> Gesendet: 16.09.2018 00:49:39 >> Betreff: [geo] Re: Hurricane moderation >> >> Stephen, I'd direct your editors to Kerry Emmanuel's seminal paper on >> hurricane track cooling, as the published basis for considering both >> hurricane track cloud nucleation and sea surface albedo modulation to >> moderate strorms >> >> On Saturday, September 15, 2018 at 4:19:10 AM UTC-4, Stephen Salter wrote: >>> >>> Hi All >>> >>> I was asked to write something about hurricanes for a well known popular >>> news outlet but they thought that it was too technical. However it might >>> still be useful. I hope that the ETC group can comment. >>> >>> The formation of a hurricane depends on many factors including >>> atmospheric water vapour, distance from the equator and the recent history >>> of wind patterns. But an essential requirement is a high sea surface >>> temperature. To get from a tropical storm to the lowest category of >>> hurricane requires a temperature of 26.5 C. We can moderate >>> hurricanes, or even prevent them, by reducing water temperature. >>> >>> A useful start to any engineering project is the estimation of all the >>> energy flows. One cubic metre of air at a temperature of 30 C can hold >>> about 30 grams of water vapour. The energy to evaporate this is about the >>> same as in 13 grams of TNT, enough for a nasty anti-personnel mine. A >>> cubic kilometre of such air contains the same energy as the Hiroshima bomb. >>> >>> Hurricanes can be hundreds of kilometres in diameter and so contain tens >>> of thousands of Hiroshimas. If you have read this far you will know >>> about the billions of lost dollars and thousands of deaths from this amount >>> of energy. >>> >>> Most of the hurricanes that reach America (with the exception of >>> Harvey), start on the African side of the Atlantic near Cape Verde and grow >>> as they move west. We can use Google Earth to measure the hurricane >>> breeding area. The US National Weather Service gives a warm water >>> depth of 45 metres. To cool this volume by 2 C in 200 days needs more than >>> 600 times the mean US electricity power generation. If you want to moderate >>> a hurricane tomorrow, today is much too late. You should have started >>> last November. >>> >>> All this heat has come from the sun. Some could be reflected back out >>> to space by clouds. The reflectivity of clouds was studied by Sean Twomey. >>> He flew over many clouds, scooped samples and measured the solar energy >>> reflected from their tops. He showed that reflectivity depends on the >>> size distribution of drops. Lots of small drops reflect more than the >>> same amount of liquid water in fewer, larger ones. In typical >>> conditions, doubling the cloud drop number increases reflectivity by a bit >>> over 0.05. >>> >>> Making cloud drops needs a high humidity but also some kind of ‘seed’ >>> called a condensation nucleus on which to start growth. There are >>> thousands of condensation nuclei per cubic centimetre of air over land but >>> fewer in air over mid ocean, often less than 50. John Latham suggested that >>> the salt residues left from the evaporation of a spray of sub-micron drops >>> of sea water would be excellent condensation nuclei. They would be moved >>> from the sea surface by turbulence to produce a fairly even distribution >>> upwards through the marine boundary layer to where clouds form. >>> >>> The condensation nuclei could be produced by wind-driven sailing vessels >>> cruising along the hurricane breeding areas getting energy from their >>> motion through the water. We can make spray by pumping water through very >>> small nozzles etched in the silicon wafers used for making microchips. The >>> main technical problem is that sea water is full of plankton much larger >>> than nozzles. This can be filtered using ultra-filtration technology >>> with back-flushing, originally developed for removing polio viruses from >>> drinking water. Each vessel would produce 0.8 micron diameter drops at 10 >>> 17 a second. >>> >>> Spray operations would depend on the pattern of sea surface temperatures >>> as measured by satellites. We want the trajectory of temperature rises >>> through the year from November to the following July to be those that an >>> international panel of meteorologists think will give a desirable rainfall >>> pattern from ‘gentle’ tropical storms. >>> >>> Most ships are made in quite small numbers. An exception was the >>> Flower class corvettes built for the Royal Navy during World War II. If we >>> index-link the 1940 cost to today we can predict that in mass production >>> each spray vessel would cost $4 million. With assumptions which have not >>> yet been rejected by hurricane experts, we think that controlling the >>> Atlantic hurricane breeding paths would need about 100 vessels. With >>> typical ship lifetime the annual ownership and maintenance cost would be >>> about $40 million. If these figures and recent estimates of the cost of >>> hurricane damage are correct the benefit-to-cost ratio is quite attractive. >>> >>> >>> >>> Because of official UK Government policy updated in May 2018 the project >>> is privately funded. >>> >>> I will send anyone who asks an update on recent hardware development, >>> still privately funded. >>> >>> Stephen >>> >>> >>> -- >>> Emeritus Professor of Engineering Design, School of Engineering, >>> Mayfield Road, University of Edinburgh EH9 3DW, Scotland >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "geoengineering" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at https://groups.google.com/group/geoengineering. >> For more options, visit https://groups.google.com/d/optout. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "geoengineering" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at https://groups.google.com/group/geoengineering. >> For more options, visit https://groups.google.com/d/optout. >> > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. 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