Cooling: Solar Radiation Management


     The biggest form of geo-engineering is adding vast amounts of CO2 to the air.

     That causes huge damages, most of them delayed,

     The graph of energy intensity (density) radiated to space by Earth, on the vertical axis, correponds to frequency on the bottom and wavelength on the top.   Less is radiated to space in the absorption bands of the principal greenhouse gases (GHGs).  The principal atmospheric window thru GHGs is 10 to 12 µm.  320 K, the top "curve", = 47°C = 117°F.       22°C MODTRAN Model with Tropical setting = 295 K = 72°F.

     The figures below show the increase in absrobed solar radiation over time and space.  The left graphs shows that, over 20 years, Earth has absorbed more solar radiation - it has been getting darker (less reflective) - over the 3 major ocean basins.  Especially over the North Pacififc and North Atlantic.

     Changes over land are not shown.

Dr. Fry's summary of leading SRM methods.

     An HPAC member's take on relative effectiveness of 9 methods to cool the planet (atmosphere mostly).  Marine Cloud Brightening is rated top, followed by atmospheric methane oxidation.

Below, as above, SAI = Stratospheric Aerosol Injection (what major volcanic eruptions do) and MCB = Marine Cloud Brightening.  CH4 is Methane, the leading Well Mixed Greenhouse Gas besides CO2.

2023-24 Articles

Dimming the Sun to Cool the Earth - Is Solar Geo-Engineering the Future? 0524

Autonomous Solar-Powered Catamarans to Enhance Marine Cloud Brightening 0524

Cloud Cover Is Easier to Affect than Previously Thought 0524

Humans Might Need to Re-Engineer the Climate 0424 - Washington Post editorial

Geo-Engineering Could Save the Ice Sheets – but Only if We Start Soon 0424

Radical Experiment Shows Cloud Brightening May Be Climate’s White Knight 0424

AMR’s Technical Solution to Cool Global Climate by 0.5-1.0°C within 20-25 Years 0424

Cloud Engineering Could Be More Effective against Global Warming than Previously Thought 0424

How Cloud Brightening Might Save the Great Barrier Reef 0424

NOAA Calls for Urgent Investigation into Carbon Removal and Brightening Earth 0324

Warming Is Getting Worse. So They Just Tested a Way to Deflect the Sun. 0424

Geo-Engineering Faces Backlash over Regulatory Gaps and Unknown Risks 0324

Pumping Seawater over Frozen Ocean to Save the Arctic's Sea Ice 0324

Dehydrate the Stratosphere to Curb Global Warming? 0224

Could a Giant Parasol in Outer Space Help Solve the Climate Crisis? 0224

How ‘Cooling Glass’ Could Reflect Solar Radiation Back into Space 0124

What Are Main Global Solar Radiation Modification (SRM) Technologies? Why? 0923

Stratospheric Aerosol Injection (SAI) in the North Warms Ocean at Antarctic Ice Shelves, but SAI in the South Cools Them 0623

Experts Call for Global Moratorium on Efforts to Geo-Engineer Climate 0923

What You Need to Know about Reflecting Sunlight to Cool Earth 0823 - emphasis on most developed method, imitating volcanoes by injecting aerosols into the stratosphere

Solar Geo-Engineering — Climate Solution or Pandora's Box? 0723

Chinese Scientists Are Trying to Shield Melting Glaciers From the Sun 0723

White House Cautiously Opens Door to Blocking Sun’s Rays to Cool Earth 0723

EU Looks into Blocking Out the Sun, as Climate Efforts Falter 0623

Spies Worry that a Sun-Blocking ‘Climate Solution’ Could Trigger War 0223

Study Reflecting Sunlight to Cool Earth before Climate Change Gets Much Worse, Urge 60 Scientists 0223

Why Billionaires Are Obsessed with Blocking Out the Sun 0223

George Soros Sees Arctic Threat to Civilization Survival, Wants Geo-Engineering 0223

Solar Radiation Management – Key Climate Solution or Path to Catastrophe? 0223

Startup Offers Stratospheric Geo-engineering as a Service 1222

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White House Pushes Ahead Research to Cool Earth by Reflecting Back Sunlight 1022

Can This Ice-Making Submarine Save The Arctic? 0622

Dimming the Sun Could Expose 1 Billion More People to Malaria 0422 - by decreasing the area that is too hot for malaria

Weird Ideas to Fix the Climate Crisis Might Be All We Have 1021

What’s the Least Bad Way to Cool the Planet?1021

Opponents of Geo-Engineering Misunderstand Humanity’s Choices 0621

National Academy of Scientists Supports Reflecting the Sun’s Rays 0321

We Must Start Refreezing the Arctic Ocean Very Soon to Save Our Megacities 0121

As Earth Warms Faster, Scientists Eye Solar Radiation Management to Cool Off 0121

As Climate Disasters Pile Up, Solar Radiation Management Plan Gains Traction 1020

Scientists Trial Cloud Brightening Equipment to Shade, Cool Great Barrier Reef 0420

Heat the Arctic to Cool the Earth, Some Scientists Say 1219 - so sea ice disappears, allowing heat from ocean below to escape into space.  How does that interact with albedo change from light ice to dark water?

Pumping Seawater atop Sea Ice to Refreeze Arctic Sea Ice Isn't the Best Idea 1219

Can Arctic 'Ice Management' Combat Climate Change? 1219

Ancient Upheavals Show How to Geo-Engineer a Stable Climate 0619 - in-depth (for news article) review of paleoclimate relevant to today, and of geo-engineering methods, both CO2 removal and soalr radiation management.

Geo-Engineer the Planet?  More Scientists Now Say It Must Be an Option 0519

Plan to Artificially Cool Earth's Climate Could Be Safe, Study Finds 0319

Solar Radiation Management May Not Cool the Oceans, Study Says 1018

Geo-Engineering Problem - Dimming the Sky Won’t Save the World’s Harvests 0818

The Best Way to Shade Earth 0718 - Inject sulfates (into stratosphere) in sub-tropics to mid-latitudes, not near the equator.

2 Audacious Plans for Saving the World’s Ice Sheets 0518

Could Sprinkling Sand Save the Arctic's Shrinking Sea Ice? 0418

Developing Nations to Study Ways to Dim Sunshine, Slow Warming 0418

What on Earth?  Why Climate Change Skeptics Are Backing Geo-Engineering 0318

Geo-Engineer Polar Glaciers to Slow Sea-Level Rise 0318 - Make them whiter, or thicker.

“Can We Refreeze the Arctic?”, Scientists Are Beginning to Ask 0318

Case against Geo-Engineering 1117 - PDF, 80 pp

4 Radical Plans to Save Civilization from Climate Change 0917 - merely a quick summary: 3 are SRM, 1 CDR.
carbon vacuums (CDR), salt-spraying ships (clouds), sparkle-blasting ballons (stratospheric sulfates), and super-sized space mirrors

Scientists Dim Sunlight, Suck Up CO2 to Cool Planet 0717

A Cirrus Cloud Climate Dial? 0717

Should We Geo-Engineer Earth to Halt Warming?  Scientists Say Maybe 0717

US Scientists Launch World's Biggest Solar Geo-Engineering Study 0317

Could a £400 Billion Plan to Refreeze the Arctic before the Ice Melts Really Work? 0217

White House Urges Research on Geo-Engineering to Combat Global Warming 0117

How Does Albedo Affect Climate? 0423

     Earth is getting darker, which makes it absorb more heat, and thus warm up.  Warming is not just from greenhouse gases.  However, the changing albedo was at least initiated by adding greenhouse gases.

Can Geoengineering Fix the Climate? 100s of Scientists Say Not So Fast. 1222

At right, observe that the dark forest (mesic savanna) reflects less sunlight than the semi-arid savanna or the aird savanna.  The more arid conditions will have a net cooling effect, other things equal.  

What Could We Do Specifically to Cool the Arctic? 0822

2 methods reviewed: stratospheric aerosol injection and marine cloud brightening

2016 Articles and earlier

Scientists Want to Give the Atmosphere an Antacid to Relieve Climate Change 1216 - calcium carbonates intead of sulfates

Geo-Engineering to Alter Climate Moves Closer to Reality 1016

Ocean Warming due to Plankton Collapse 0616 - The fewer plankton make correspondingly less dimethyl sulfide, which serve as important cloud condensation nuclei to form cooling cloouds near the ocean surface.

Sea Level Rise?  Can We Pump Quadrillions of Tons of Seawater 2 Miles High? 0316

Massive Tree Farms, Soil Carbon Sequestration May Be Really Bad Climate Ideas 0216

Could Bright, Foamy Wakes from Ocean Ships Combat Global Warming? 0116                                     

Nanostructure and Nanonet Solar Cells, CCS, SRM Could Slow Climate Change 1215

Could the Smell of the Sea Help Cool a Warming Planet? 0815

Geo-Engineering Will Not Save Ocean Life from Centuries of Acidification 0815

Cloud Brightening Experiment Tests Tool to Slow Climate Change 0715

‘Last Ditch’ Climate Change Remedies, Olivine & Biochar, Remove CO2 from Air 0615

Whitening Arctic Ocean Surface to Reflect Sunlight into Space Will Fail 0415

Warning over Aerosol Climate Fix 0415

Scientists Urge Global ‘Wake-up Call' to Deal with Climate Change 0215

Planet Reboot - Fighting Climate Change With Geo-Engineering 1214

Geo-Engineering - Climate Fixes ‘Could Harm Billions' 1114

Many Experts Say Technology Can't Fix Climate Change 1114

Climate Engineering - Minor Potential, Major Side Effects 0214

If You Start Geo-Engineering to Halt Global Warming, Don't Stop 1213

Let's Play God - Experiments That Might Save (or Destroy) the World 1013

IPCC Climate Report Puts Geo-Engineering in the Spotlight 1013

Central Intelligence Agency Studies Geo-Engineering 0713

Earth-Cooling Schemes May Devastate, Need Global Sign-off 0313 - Solar Radiation Management, chiefly sulfates in the stratosphere - spread droughts and deserts to new areas

Geo-Engineering Responses to Rapidly Shrinking Arctic Ice Cap 0213 

Get Cirrus in the Fight Against Climate Change 0113 

Altering Clouds to Fight Climate Change 0113 

Algae Farming for Climate Change a Big Waste of Money 1212 

Overview of Geo-Engineering 1112 - introduction to amounts (efficacy) and costs, for 12 methods

 Geo-Engineering Interest Grows 1110

Geo-Engineering Poses Drought Risk 0809 - 4 of the 5 methods discussed do not involve biological actors.

Geo-Engineering to Slow Warming 1106 - 5 methods discussed or mentioned

The figure shows 4 types of SRM and 4 types of CO2 removal.

       Add to the diagram storing carbon in soils, via (1) rapid (~1 week / small pasture) rotation grazing, (2) no-till farming, especially organic farming, and (3) biochar.

     LIke foresting, these requires large land areas, but they (especially grazing) work much better in dry areas, which will grow some grass but few or no trees.  Like foresting, these are already being used, at negligible cost.  Moreover, soils generally store more carbon per acre than standing biomass (e.g., forests), especially toward the poles.  (But near the equator, standing biomass stores much more than the soil there, except in peatlands.)

Section Map: Reversing Climate Change