Century-Scale Effect of Climate Change on Meteorite Falls

Abstract

Climate change is inducing a global atmospheric contraction above the tropopause (~10 km), leading to systematic decrease in neutral air density. The impact of climate change on small meteoroids has already been observed over the last two decades, with documented shifts in their ablation altitudes in the mesosphere (~50-85 km) and lower thermosphere (~85-120 km). This study evaluates the potential effect of these changes on meteorite-dropping fireballs, which typically penetrate the stratosphere (~10-50 km). As a case study, we simulate the atmospheric entry of the fragile Winchcombe carbonaceous chondrite under projected atmospheric conditions for the year 2100 assuming a moderate future emission scenario. Using a semi-empirical fragmentation and ablation model, we compare the meteoroid's light curve and deceleration under present and future atmospheric density profiles. The results indicate a modest variation of the ablation heights, with the catastrophic fragmentation occurring 300 m lower and the luminous flight terminating 190 m higher. The absolute magnitude peak remains unchanged, but the fireball would appear 0.5 dimmer above ~120 km. The surviving meteorite mass is reduced by only 0.1 g. Our findings indicate that century-scale variations in atmospheric density caused by climate change moderately influence bright fireballs and have a minimal impact on meteorite survival.

Accepted in Meteoritics & Planetary Science

References in corpus (11)

• Compositional distributions and evolutionary processes for the near-Earth object population: Results from the MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS
• The Global Meteor Network -- Methodology and First Results
• A Global Fireball Observatory
• Two Strengths of Ordinary Chondritic Meteoroids as Derived from their Atmospheric Fragmentation Modeling
• The Maribo CM2 meteorite fall - survival of weak material at high entry speed
• Source regions of carbonaceous meteorites and NEOs
• Small Near-Earth Asteroids as a Source of Meteorites
• The January 7, 2015, superbolide over Romania and structural diversity of meter-sized asteroids
• High precision meteor observations with the Canadian Automated Meteor Observatory -- Data reduction pipeline and application to meteoroid mechanical strength measurements
• Direct measurement of decimeter-sized rocky material in the Oort cloud
• Perihelion history and atmospheric survival as primary drivers of the Earth`s meteorite record