Classification of aerosol-cloud interaction regimes over Tokyo

Ryohei Misumi, Yasushi Uji, Kazuhiko Miura, Tatsuhiro Mori, Yutaka Tobo, Yoko Iwamoto

Research output: Contribution to journalArticlepeer-review

Abstract

Previous studies on the aerosol indirect effect have demonstrated that there are three regimes (aerosol-limited, updraft-limited, and transitional regimes). However, this classification of regimes has not been widely used in field observations as it requires measurements of updraft or supersaturation near the cloud base (Smax), which are not easy to perform. In this study, we attempted to classify the regimes using the effective supersaturation (Seff) which is relatively easy to estimate by matching cloud droplet number concentration (Nc) and supersaturation spectra of cloud condensation nuclei. Parcel model simulations were performed to examine the suitability of Seff as a proxy for Smax. Further, 35 low-level cloud cases observed around 458 m over Tokyo were classified into three regimes. In the aerosol-limited regime, Nc increased more rapidly with an increment of aerosols than in the other two regimes, indicating that the regime classification using Seff was sufficiently robust. The aerosol-limited regime in Tokyo appeared frequently when northerly winds prevailed, indicating the impact of local pollution sources around Tokyo on the aerosol cloud interaction. The results imply that anthropogenic aerosol emissions affect the climate of Tokyo.

Original languageEnglish
Article number106150
JournalAtmospheric Research
Volume272
DOIs
Publication statusPublished - 2022 Jul
Externally publishedYes

Keywords

  • Aerosol-indirect effect
  • Aerosol-limited regime
  • Cloud droplet
  • Tokyo Skytree

ASJC Scopus subject areas

  • Atmospheric Science

Fingerprint

Dive into the research topics of 'Classification of aerosol-cloud interaction regimes over Tokyo'. Together they form a unique fingerprint.

Cite this