Insights on Tropical High-Cloud Radiative Effect from a New Conceptual Model DOI
Jakob Deutloff, Stefan A. Buehler, Manfred Brath

et al.

Authorea (Authorea), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 7, 2024

The new capabilities of global storm-resolving models to resolve individual clouds allow for a more physical perspective on the tropical high-cloud radiative effect and how it might change with warming. In this study, we develop conceptual model as function cloud thickness measured by ice water path. We use atmospheric profiles from ICON simulation 5 km horizontal grid spacing calculate radiation offline ARTS line-by-line transfer model. reveals that is sufficient approximate high single layer characterised an albedo, emissivity temperature, which vary increase short-wave path solely explained albedo. long-wave governed below 10-1 kg m-2, decrease temperature increasing above threshold. total simulations chosen day run 2.59 W closely matched our 2.56 m-2. Because depends assumed alternative, assumptions low make substantial difference. predicts doubling fraction causes effect.

Language: Английский

A systematic evaluation of high-cloud controlling factors DOI Creative Commons
Sarah Wilson Kemsley, Paulo Ceppi, Hendrik Andersen

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(14), P. 8295 - 8316

Published: July 24, 2024

Abstract. Clouds strongly modulate the top-of-the-atmosphere energy budget and are a major source of uncertainty in climate projections. “Cloud controlling factor” (CCF) analysis derives relationships between large-scale meteorological drivers cloud radiative anomalies, which can be used to constrain feedback. However, choice CCFs is crucial for meaningful constraint. While there rich literature investigating ideal CCF setups low-level clouds, lack analogous research explicitly targeting high clouds. Here, we use ridge regression systematically evaluate addition five candidate previously established core within large spatial domains predict longwave high-cloud anomalies: upper-tropospheric static stability (SUT), sub-cloud moist energy, convective available potential inhibition, wind shear (ΔU300). We identify an optimal configuration predicting anomalies that includes SUT ΔU300 show domain size more important than selection predictive skill. also find discrepancy sizes required locally globally aggregated anomalies. Finally, scientifically interpret coefficients, where captures physical known feedbacks deduce inclusion into observational constraint frameworks may reduce associated with changes anvil amount as function change. Therefore, highlight clouds

Language: Английский

Citations

4
Symmetry in Mesoscale Circulations Explains Weak Impact of Trade Cumulus Self‐Organization on the Radiation Budget in Large‐Eddy Simulations DOI Creative Commons
Martin Janssens, Fredrik Jansson, Pouriya Alinaghi

et al.

Geophysical Research Letters, Journal Year: 2025, Volume and Issue: 52(3)

Published: Feb. 1, 2025

Abstract We investigate if mesoscale self‐organisation of trade cumuli in 150 km‐domain large‐eddy simulations modifies the top‐of‐atmosphere radiation budget relative to 10 simulations, across 77 characteristic, idealized environments. In large domains, self‐generated circulations produce fewer, larger and deeper clouds, raising cloud albedo. Yet they also precipitate more than small‐domain cumuli, drying warming layer, reducing cover. Consequently, domains cool slightly less through shortwave cloud‐radiative effect, clear‐sky outgoing longwave radiation, for a net cooling (−0.5 W ). This is generally smaller large‐domain radiation's sensitivity large‐scale meteorological variability, which similar observations. Hence, would not alter weak trade‐cumulus feedback estimates previously derived from simulations. explain this with symmetry hypothesis: ascending descending branches symmetrically increase reduce cloudiness, weakly modifying mean budget.

Language: Английский

Citations

0
Insights on Tropical High‐Cloud Radiative Effect From a New Conceptual Model DOI Creative Commons
Jakob Deutloff, Stefan A. Buehler, Manfred Brath

et al.

Journal of Advances in Modeling Earth Systems, Journal Year: 2025, Volume and Issue: 17(2)

Published: Feb. 1, 2025

Abstract The new capabilities of global storm‐resolving models to resolve individual clouds allow for a more physical perspective on the tropical high‐cloud radiative effect and how it might change with warming. In this study, we develop conceptual model as function cloud thickness measured by ice water path. We use atmospheric profiles from ICON simulation horizontal grid spacing calculate radiation offline ARTS line‐by‐line transfer model. reveals that is sufficient approximate high single layer characterized an albedo, emissivity temperature, which vary increase short‐wave path solely explained albedo. long‐wave governed below , decrease temperature increasing above threshold. mean simulations chosen day run closely matched our . Because depends assumed alternative, assumptions low make substantial difference. predicts doubling fraction roughly doubles positive effect.

Language: Английский

Citations

0
Dissecting cirrus clouds: navigating effects of turbulence on homogeneous ice formation DOI Creative Commons
B. Kärcher, Fabian Hoffmann, Adam B. Sokol

et al.

npj Climate and Atmospheric Science, Journal Year: 2025, Volume and Issue: 8(1)

Published: April 5, 2025

Language: Английский

Citations

0
Climate Models Underestimate Global Decreases in High‐Cloud Amount With Warming DOI Creative Commons
Sarah Wilson Kemsley, Peer Nowack, Paulo Ceppi

et al.

Geophysical Research Letters, Journal Year: 2025, Volume and Issue: 52(7)

Published: April 9, 2025

Abstract Cloud feedback has prevailed as a leading source of uncertainty in climate model projections under increasing atmospheric carbon dioxide. Cloud‐controlling factor (CCF) analysis is an approach used to observationally constrain cloud feedback, and subsequently the sensitivity. Although high clouds contribute significantly toward uncertainty, they have received comparatively little attention CCF other observational analyses. Here we use for first time ‐cloud radiative focusing on amount component owing its dominant contribution high‐cloud feedback. Globally, observations indicate larger decreases cloudiness than state‐of‐the‐art models suggest. In fact, half 16 considered here predict feedbacks inconsistent with observations, likely due misrepresenting stability iris mechanism. Despite suggested strong warming, point near‐neutral net almost canceling longwave shortwave contributions.

Language: Английский

Citations

0
Tropical Cirrus in Global‐Storm Resolving Models: 3. Seasonal Changes and TTL Cirrus in the Tropical Western Pacific Using DYAMOND DOI Creative Commons
Samantha M Turbeville, Thomas P. Ackerman, Peter N. Blossey

et al.

Earth and Space Science, Journal Year: 2025, Volume and Issue: 12(4)

Published: April 1, 2025

Abstract Recent advances in computer modeling have spurred the production of several global storm‐resolving models (GSRMs), which explicitly represent atmospheric circulations from convective to scales. As a result, GSRMs simulate formation and evolution tropical cirrus clouds more physically than typical climate models/general circulation (GCMs) use parameterizations deep convection. We analyze output nine DYAMOND initiative, focusing on second phase that simulated period January–February 2020. This paper is third series investigating using model for an intercomparison. In tropics, capture mean outgoing longwave radiation within −5 14 W m −2 observed climatology, though most precipitation over 40‐day simulation observed. While large‐scale convection with some fidelity, large regional differences cloud properties top‐of‐atmosphere fluxes exist. focus region Tropical Western Pacific study small‐scale features available high spatiotemporal resolution GSRMs. Most participated both phases seasonal between two phases, yet each exhibits unique populations are persistent across seasons. even notoriously difficult‐to‐observe tropopause layer (TTL) cirrus, providing novel perspective TTL different characteristics short 40‐days simulation.

Language: Английский

Citations

0
Anvil–radiation diurnal interaction: shortwave radiative-heating destabilization driving the diurnal variation of convective anvil outflow and its modulation on the radiative cancellation DOI Creative Commons
Zhenquan Wang

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(9), P. 5021 - 5039

Published: May 15, 2025

Abstract. The behavior of convection producing anvil clouds is neither well derived from current available observations nor represented in models. In this work, a novel convective cloud data product designed to capture the outflow. Convective organizations and life stages are images infrared brightness temperature (BT) geostationary (GEO) satellites based on variable-BT segment-tracking algorithm, which allows possibility for quantifying Vertical structures measured by sensors A-Train constellation, provides cross section Here, GEO-based tracking A-Train-detected vertical profiles combined develop comprehensive GEO–A-Train Merged (GATM) investigating process On basis Lagrangian-view GATM data, production mesoscale systems (MCSs) can be quantified. results show that daytime MCSs produce more than nighttime MCSs. During daytime, shortwave radiative heating strongly destabilizes MCS top promote outflow with strong divergence, whereas divergence driven longwave cooling through destabilization circulation weak. Moreover, assessed sensitivity budget diurnal-cycle phase shift approximately −1 W m−2 h−1 when range between −4 8 h (otherwise has same magnitude but positive). Stronger amplitude further amplify sensitivity. Overall, work presents observed anvil–radiation diurnal interaction process: determines variation outflow; turn, Earth's budget.

Language: Английский

Citations

0
High clouds and higher sensitivity DOI
Aiko Voigt

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(5), P. 370 - 371

Published: May 1, 2024

Language: Английский

Citations

1
Factors determining tropical upper-level cloud radiative effect in the radiative-convective equilibrium framework DOI Creative Commons

Hyoji Kang,

Yong-Sang Choi,

Jonathan H. Jiang

et al.

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: June 11, 2024

Abstract Investigation of the major factors determining tropical upper-level cloud radiative effect (TUCRE) is crucial for understanding feedback mechanisms. We examined TUCRE inferred from outputs historical runs and AMIP CMIP6 models employing a radiative-convective equilibrium (RCE). In this study, we incorporated RCE model configurations atmospheric dynamics thermodynamics climate models, while simplifying intricate systems. Using model, adjusted global mean surface temperature to achieve energy balance, considering variations in fraction, regional reflectivity, emission corresponding each model. Subsequently, was calculated as unit K/%, representing change (K) response an increment clouds (%). Our simulation indicates that are temperatures moist-cloudy moist-clear regions, well fraction clouds. The higher determination coefficients between both moist regions attributable their contribution trapping on outgoing longwave radiations, which predominantly determines TUCRE. Consequently, results study underscore importance accurately enhance representation models.

Language: Английский

Citations

1
Insights on Tropical High-Cloud Radiative Effect from a New Conceptual Model DOI
Jakob Deutloff, Stefan A. Buehler, Manfred Brath

et al.

Authorea (Authorea), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 7, 2024

The new capabilities of global storm-resolving models to resolve individual clouds allow for a more physical perspective on the tropical high-cloud radiative effect and how it might change with warming. In this study, we develop conceptual model as function cloud thickness measured by ice water path. We use atmospheric profiles from ICON simulation 5 km horizontal grid spacing calculate radiation offline ARTS line-by-line transfer model. reveals that is sufficient approximate high single layer characterised an albedo, emissivity temperature, which vary increase short-wave path solely explained albedo. long-wave governed below 10-1 kg m-2, decrease temperature increasing above threshold. total simulations chosen day run 2.59 W closely matched our 2.56 m-2. Because depends assumed alternative, assumptions low make substantial difference. predicts doubling fraction causes effect.

Language: Английский

Citations

0