Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates
Seeley and Wordsworth (2021) showed that in small-domain cloud-resolving simulations the pattern of precipitation transforms in extremely hot climates (≥320 K) from quasi-steady to organized episodic deluges, with outbursts of heavy rain alternating with several dry days. They proposed a mechanism f...
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2023
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Online Access: | http://dx.doi.org/10.22541/essoar.169008309.90443492/v1 |
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crwinnower:10.22541/essoar.169008309.90443492/v1 2024-06-02T08:13:30+00:00 Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates Song, Xinyi Abbot, Dorian Schuyler Yang, Jun 2023 http://dx.doi.org/10.22541/essoar.169008309.90443492/v1 unknown Authorea, Inc. posted-content 2023 crwinnower https://doi.org/10.22541/essoar.169008309.90443492/v1 2024-05-07T14:19:16Z Seeley and Wordsworth (2021) showed that in small-domain cloud-resolving simulations the pattern of precipitation transforms in extremely hot climates (≥320 K) from quasi-steady to organized episodic deluges, with outbursts of heavy rain alternating with several dry days. They proposed a mechanism for this transition involving increased water vapor absorption of solar radiation leading to net lower-tropospheric radiative heating. This heating inhibits lower-tropospheric convection and decouples the boundary layer from the upper troposphere during the dry phase, allowing lower-tropospheric moist static energy to build until it discharges, resulting in a deluge. We perform cloud-resolving simulations in polar night and show that the same transition occurs, implying that some revision of their mechanism is necessary. We show that episodic deluges can occur even if the lower-tropospheric radiative heating rate is negative, as long as the magnitude of the upper-tropospheric radiative cooling is about twice as large. We find that in the episodic deluge regime the mean precipitation can be inferred from the atmospheric column energy budget and the period can be predicted from the time for radiation and reevaporation to cool the lower atmosphere. Other/Unknown Material polar night The Winnower |
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Seeley and Wordsworth (2021) showed that in small-domain cloud-resolving simulations the pattern of precipitation transforms in extremely hot climates (≥320 K) from quasi-steady to organized episodic deluges, with outbursts of heavy rain alternating with several dry days. They proposed a mechanism for this transition involving increased water vapor absorption of solar radiation leading to net lower-tropospheric radiative heating. This heating inhibits lower-tropospheric convection and decouples the boundary layer from the upper troposphere during the dry phase, allowing lower-tropospheric moist static energy to build until it discharges, resulting in a deluge. We perform cloud-resolving simulations in polar night and show that the same transition occurs, implying that some revision of their mechanism is necessary. We show that episodic deluges can occur even if the lower-tropospheric radiative heating rate is negative, as long as the magnitude of the upper-tropospheric radiative cooling is about twice as large. We find that in the episodic deluge regime the mean precipitation can be inferred from the atmospheric column energy budget and the period can be predicted from the time for radiation and reevaporation to cool the lower atmosphere. |
format |
Other/Unknown Material |
author |
Song, Xinyi Abbot, Dorian Schuyler Yang, Jun |
spellingShingle |
Song, Xinyi Abbot, Dorian Schuyler Yang, Jun Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
author_facet |
Song, Xinyi Abbot, Dorian Schuyler Yang, Jun |
author_sort |
Song, Xinyi |
title |
Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
title_short |
Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
title_full |
Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
title_fullStr |
Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
title_full_unstemmed |
Critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
title_sort |
critical role of vertical radiative cooling contrast in triggering episodic deluges in small-domain hothouse climates |
publisher |
Authorea, Inc. |
publishDate |
2023 |
url |
http://dx.doi.org/10.22541/essoar.169008309.90443492/v1 |
genre |
polar night |
genre_facet |
polar night |
op_doi |
https://doi.org/10.22541/essoar.169008309.90443492/v1 |
_version_ |
1800737037078233088 |