More evidence that global warming is a hoax and climate change is a religion!
We still know far too little about the highly complex natural phenomenon called climate! Climate change has become a major subject for demagogues and profiteers!
"Some of the particles with the biggest impact on stratospheric chemistry are so small they have remained mostly invisible to scientists—until now.
New research in Science suggests the lower stratosphere contains tons more ultrafine aerosol particles than previously thought; they are carried upward by rising air currents and atmospheric mixing from the troposphere, the lowest layer of Earth’s atmosphere. Despite their tiny size, the specks add up to large amounts of surface area where atmospheric reactions can occur, some of which can break down ozone and scatter sunlight.
To study these hard-to-detect particles, researchers used instruments aboard NASA’s WB-57 high-altitude research aircraft during the Stratospheric Aerosol Processes, Budget, and Radiative Effects (SABRE) mission in 2023, and measured aerosols up to 19 kilometers above Earth. Particles smaller than 150 nanometers across made up most of the total aerosol surface area, accounting for as much as 90% of the surface area in some regions.
These sub-150-nanometer particles also acted like sponges for condensable vapors: Gases that might otherwise form new aerosols or bulk up larger ones instead stuck to the tiny particles. As they aged, the specks collided, clumped together, and gradually grew larger and fewer. ..."
From the editor's summary and abstract:
"Editor’s summary
The lower stratosphere is rife with a class of extremely small aerosols rich in organic compounds that have been largely underappreciated until now. Lyu et al. showed that these particles, most of which originate in and are transported from the troposphere, dominate the surface area available for heterogeneous chemistry and constitute the major sink for condensable vapors. The consequences of these particles on heterogeneous chemistry and aerosol microphysical processes in the lower stratosphere may be considerable, particularly for geoengineering proposals that involve injecting aerosol precursors into the stratosphere. ...
Structured Abstract
INTRODUCTION
The lower stratosphere is a complex and fascinating region of the atmosphere where air from the troposphere below enters and mixes with air that has been in the stratosphere for years. This region is particularly important to climate and atmospheric chemistry because aerosol particles scatter solar radiation and provide surfaces for heterogeneous reactions that affect stratospheric ozone. Further, many proposed albedo modification by stratospheric aerosol injection (SAI) efforts, a form of “geoengineering,” would emit aerosol particles or precursors in this region of the stratosphere to scatter more sunlight to space and cool Earth’s surface. A thorough understanding of the processes that govern aerosol sources, sinks, and characteristics in the lower stratosphere is essential to understand these effects.
RATIONALE
... Therefore, previous measurements have not accurately determined the surface area of these nanoparticles nor quantified their evolution in the stratosphere.
RESULTS
Using multiple instruments on a high-altitude research aircraft, we measured the size distribution and composition of particles in the lower stratosphere at altitudes up to 19 km. Particles with diameters <150 nm dominated the aerosol surface area. These small particles mixed and coagulated with the larger stratosphere background particles, resulting in a bimodal size distribution in the lower stratosphere.
A chemistry-climate model did not replicate this bimodal size distribution.
Our measurements show two distinct sources for the small-particle mode. In older stratospheric air they are sulfuric acid with metals from meteors. In younger stratospheric air influenced by the troposphere, the small-particle mode is mostly tropospheric particles with high organic content, which will affect their reactivity with gas-phase species.
CONCLUSION
This work provides well-resolved measurements of sub–150-nm particles in the lower extratropical stratosphere over a wide range of stratospheric ages. Because the small particles were observed previously in limited observations in stratospheric air at altitudes <13 km, as well as in earlier test flights for this study, this bimodal structure is likely a consistent feature of the extratropical lower stratosphere. ..."
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