🚨An analysis of forest-based projects funded through the sale of #CarbonCredits shows that 10% of them may have a net warming effect on the climate because of the way they alter the Earth’s #albedo, or how much sunlight is reflected back into space.
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2/ Albedo is how much sunlight Earth’s surface reflects vs. absorbs
Forests are darker than grass or snow, meaning they absorb more heat
So when grasslands or snowy areas are turned into forests, Earth’s surface can absorb more heat, partly cancelling out cooling effect of #CDR
3/ So, this study analyzed 172 Afforestation, Reforestation & Revegetation projects in the Voluntary Carbon Market - projects that collectively aim to deliver nearly 800 million tons of CDR over the next century.
But none of these projects’ standards account for albedo change.
4/ FINDINGS
12% of projects are in areas where albedo completely negates climate benefit
25% occur where albedo cuts benefit by half
Only 9% of projects are in regions where albedo actually enhances cooling
This means some “C neutral” projects might not be climate +ve at all
5/ These projects are spread across 5 continents and various ecosystems.
Albedo losses were highest in deserts, arid regions & temperate forests, where new trees darken bright land surfaces.
6/ In contrast, tropical regions, like moist and dry broadleaf forests or savannas, showed moderate or even positive effects.
7/ The researchers propose a 4-tier framework to help C markets correct for albedo impacts & improve integrity:
Tier 1️⃣: Prioritize planting in regions where albedo effects are minimal or positive.
Tier 2️⃣: Exclude projects if albedo cancels out ≥50–100% of the CO₂ benefit.
8/ Tier 3️⃣: Apply credit “discounts” based on each site’s albedo data.
Tier 4️⃣: Reward projects with albedo benefits (net cooling).
9/ If these adjustments were applied:
Global carbon credits from the 172 projects could drop by 30–49%, reflecting their true climate impact.
However, projects with albedo benefits could gain $59 million in extra value from their additional cooling effects.
10/ Currently, C markets only measure biochemical effects (like CO₂ captured by trees)
But biophysical effects (albedo, evapotranspiration & cloud formation) also change the planet’s energy balance
Ignoring them means overcrediting projects & undermining real climate progress
11/ Because of new remote sensing tools & global datasets, albedo accounting is now practical.
That means standards like Verra’s Verified Carbon Standard or Isometric’s protocols could start integrating albedo right away to improve transparency, study recommended.
📝For more details, read the study entitled "Accounting for albedo in carbon market protocols" here:
🚨Can buildings remove CO₂ while cooling indoor air?
A new study shows that adding CO₂ capture units (#DAC) to building cooling systems can cut energy use by over 50% & remove atmospheric carbon, even in hot, humid places.
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2/ Buildings use a lot of energy. About 37% of global energy & 40% of CO₂ emissions.
Cooling is the biggest part, taking almost 40% of building electricity.
As the planet warms, cooling demand rises, creating a vicious cycle.
3/ Direct Air Capture extracts CO₂ directly from ambient air, unlike point-source capture.
But adsorption-based DAC struggles in humid environments: water competes with CO₂ for sorbent sites, making it very energy-hungry.
🚨A new study presents the 1st structural prototype of a planetary sunshade - a large space-based system at L1 designed to block some sunlight & cool Earth.
Using solar sails, deployable booms & CubeSat-based frames, it outlines a pathway for space-based #geoengineering.🧵1/11
2/ The planetary sunshade would function as a vast array of satellites at the Sun–Earth L1 point, collectively blocking ~1.8% of incoming photons - enough to reduce global temperatures by ~2 °C.
"Unlike #SAI or orbital dust, it promises uniform, reversible cooling."
3/ The team followed European spacecraft design standards, testing different ideas with decision matrices & computer simulations (finite element analysis) to choose materials & structures that could actually survive launch.
🚨New Viewpoint published in Frontiers that responds to Siegert et al.’s paper.
While Siegert et al. warn against polar #geoengineering, Moore et al. argue for a compassionate harm-reduction paradigm, keeping geoengineering research open alongside decarbonization.
Their case: interventions are risky, may not work, and could distract from the essential task which is deep decarbonization.frontiersin.org/journals/scien…
3/ Moore et al. [] reply that this “consequences-based paradigm” (raising alarms to spur action), has dominated climate science for 50 years.
🚨New Nature Geoscience study shows that blooms of Phaeocystis antarctica (microalgae) in the Southern Ocean ~14,000 yrs ago massively drew down CO₂, stabilizing climate. Their decline today could have global consequences.
#CarbonSink #CarbonDrawdown
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2/ Microalgae are pivotal in the Southern Ocean carbon cycle.
A new study from the Alfred Wegener Institute (AWI) reveals that during the Antarctic Cold Reversal (14.7–12.7k yrs BP), algal blooms slowed the rise of atmospheric CO₂.
3/ At the end of the last ice age, the Antarctic Cold Reversal brought vast winter sea ice followed by strong spring melt.
These unique conditions fueled Phaeocystis antarctica blooms, exceptionally efficient at capturing and exporting carbon.