Investigating the Potential Atmospheric Accumulation and Radiative Impact of the Coming Increase in Satellite Reentry Frequency Journal Article uri icon

Overview

abstract

  • AbstractConstruction of numerous satellite megaconstellations in the low Earth orbit (LEO) (300–2,000 km) is projected over the coming decades. Estimates suggest that the number of satellites in an LEO could exceed 60,000 by 2040. The increase in the annual mass flux of anthropogenic material into the upper atmosphere as a result of maintaining these megaconstellations could rival the natural occurring meteoric mass flux. Little is known about the aerosols that will be produced by reentry vaporization, which makes estimating the associated impacts on climate and ozone difficult. Aluminum is a primary satellite component that will likely be emitted during reentry vaporization. In this study we simulate a reentry emission of 10 Gg/yr, assuming that all aerosols released is aluminum oxide (Al2O3). This level of Al2O3 emission is consistent with expected megaconstellation growth by 2040. We investigate how the location of atmospheric accumulation, aerosol size distribution, and radiative properties of reentry Al2O3 impacts the middle‐to‐upper atmosphere. We find that depending on reentry latitude and aerosol size distribution, a 20–40‐Gg stratospheric burden of Al2O3 aerosols accumulates poleward of 30 N/S between 10 and 30 km. Small but statistically significant changes in mesospheric heating rates lead to 1.5 K‐temperature anomalies in the mesosphere and the stratosphere at Southern Hemisphere high latitudes. These temperature anomalies are accompanied by a 10% reduction in wind speed in the Southern Hemisphere polar vortex, leading to a weaker springtime ozone hole. Some reentry scenarios also experience a strengthening of the Northern Hemisphere polar vortex.

publication date

  • March 28, 2025

Date in CU Experts

  • April 2, 2025 11:11 AM

Full Author List

  • Maloney CM; Portmann RW; Ross MN; Rosenlof KH

author count

  • 4

Other Profiles

International Standard Serial Number (ISSN)

  • 2169-897X

Electronic International Standard Serial Number (EISSN)

  • 2169-8996

Additional Document Info

volume

  • 130

issue

  • 6