The diurnal cycle of rainfall and cloud properties from Himawari-8 during the austral summer (2016-2020).

Abstract. Here, liquid water path (LWP), cloud fraction, cloud top height, and cloud base height retrieved by a suite of A-train satellite instruments (the CPR aboard CloudSat, CALIOP aboard CALIPSO, and MODIS aboard Aqua) are compared to ship observations from research cruises made in 2001 and 2003–2007 into the stratus/stratocumulus deck over the southeast Pacific Ocean. It is found that CloudSat radar-only LWP is generally too high over this region and the CloudSat/CALIPSO cloud bases are too low. This results in a relationship (LWP~h9) between CloudSat LWP and CALIPSO cloud thickness (h) that is very different from the adiabatic relationship (LWP~h2) from in situ observations. Such biases can be reduced if LWPs suspected to be contaminated by precipitation are eliminated, as determined by the maximum radar reflectivity Zmax>−15 dBZ in the apparent lower half of the cloud, and if cloud bases are determined based upon the adiabatically-determined cloud thickness (h~LWP1/2). Furthermore, comparing results from a global model (CAM3.1) to ship observations reveals that, while the simulated LWP is quite reasonable, the model cloud is too thick and too low, allowing the model to have LWPs that are almost independent of h. This model can also obtain a reasonable diurnal cycle in LWP and cloud fraction at a location roughly in the centre of this region (20° S, 85° W) but has an opposite diurnal cycle to those observed aboard ship at a location closer to the coast (20° S, 75° W). The diurnal cycle at the latter location is slightly improved in the newest version of the model (CAM4). However, the simulated clouds remain too thick and too low, as cloud bases are usually at or near the surface.

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Evaluation of the diurnal cycle of model predicted cloud properties using MSG‐SEVIRI observations

10.1063/1.3117010 ◽

2009 ◽

Author(s):

R. A. Roebeling ◽

A. Feijt ◽

E. van Meijgaard

Keyword(s):

Diurnal Cycle ◽

Cloud Properties

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Cloud Properties and Their Seasonal and Diurnal Variability from TOVS Path-B

Journal of Climate ◽

10.1175/jcli3929.1 ◽

2006 ◽

Vol 19 (21) ◽

pp. 5531-5553 ◽

Cited By ~ 93

Author(s):

C. J. Stubenrauch ◽

A. Chédin ◽

G. Rädel ◽

N. A. Scott ◽

S. Serrar

Keyword(s):

South America ◽

Diurnal Cycle ◽

Cloud Amount ◽

Early Morning ◽

Infrared Observation ◽

Relevant Variable ◽

Diurnal Variability ◽

Cloud Properties ◽

Early Afternoon ◽

The Tropics

Abstract Eight years of cloud properties retrieved from Television Infrared Observation Satellite-N (TIROS-N) Observational Vertical Sounder (TOVS) observations aboard the NOAA polar orbiting satellites are presented. The relatively high spectral resolution of these instruments in the infrared allows especially reliable cirrus identification day and night. This dataset therefore provides complementary information to the International Satellite Cloud Climatology Project (ISCCP). According to this dataset, cirrus clouds cover about 27% of the earth and 45% of the Tropics, whereas ISCCP reports 19% and 25%, respectively. Both global datasets agree within 5% on the amount of single-layer low clouds, at 30%. From 1987 to 1995, global cloud amounts remained stable to within 2%. The seasonal cycle of cloud amount is in general stronger than its diurnal cycle and it is stronger than the one of effective cloud amount, the latter the relevant variable for radiative transfer. Maximum effective low cloud amount over ocean occurs in winter in SH subtropics in the early morning hours and in NH midlatitudes without diurnal cycle. Over land in winter the maximum is in the early afternoon, accompanied in the midlatitudes by thin cirrus. Over tropical land and in the other regions in summer, the maximum of mesoscale high opaque clouds occurs in the evening. Cirrus also increases during the afternoon and persists during night and early morning. The maximum of thin cirrus is in the early afternoon, then decreases slowly while cirrus and high opaque clouds increase. TOVS extends information of ISCCP during night, indicating that high cloudiness, increasing during the afternoon, persists longer during night in the Tropics and subtropics than in midlatitudes. A comparison of seasonal and diurnal cycle of high cloud amount between South America, Africa, and Indonesia during boreal winter has shown strong similarities between the two land regions, whereas the Indonesian islands show a seasonal and diurnal behavior strongly influenced by the surrounding ocean. Deeper precipitation systems over Africa than over South America do not seem to be directly reflected in the horizontal coverage and mesoscale effective emissivity of high clouds.

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CERES Synoptic Product: Methodology and Validation of Surface Radiant Flux

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-14-00165.1 ◽

2015 ◽

Vol 32 (6) ◽

pp. 1121-1143 ◽

Cited By ~ 81

Author(s):

David A. Rutan ◽

Seiji Kato ◽

David R. Doelling ◽

Fred G. Rose ◽

Le Trang Nguyen ◽

...

Keyword(s):

Standard Deviation ◽

Diurnal Cycle ◽

Radiant Energy ◽

Energy System ◽

Surface Fluxes ◽

Radiant Flux ◽

Earth Observing System ◽

Cloud Properties ◽

Moderate Resolution Imaging Spectroradiometer ◽

Surface Observations

AbstractThe Clouds and the Earth’s Radiant Energy System Synoptic (SYN1deg), edition 3, product provides climate-quality global 3-hourly 1° × 1°gridded top of atmosphere, in-atmosphere, and surface radiant fluxes. The in-atmosphere surface fluxes are computed hourly using a radiative transfer code based upon inputs from Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS), 3-hourly geostationary (GEO) data, and meteorological assimilation data from the Goddard Earth Observing System. The GEO visible and infrared imager calibration is tied to MODIS to ensure uniform MODIS-like cloud properties across all satellite cloud datasets. Computed surface radiant fluxes are compared to surface observations at 85 globally distributed land (37) and ocean buoy (48) sites as well as several other publicly available global surface radiant flux data products. Computed monthly mean downward fluxes from SYN1deg have a bias (standard deviation) of 3.0 W m−2 (5.7%) for shortwave and −4.0 W m−2 (2.9%) for longwave compared to surface observations. The standard deviation between surface downward shortwave flux calculations and observations at the 3-hourly time scale is reduced when the diurnal cycle of cloud changes is explicitly accounted for. The improvement is smaller for surface downward longwave flux owing to an additional sensitivity to boundary layer temperature/humidity, which has a weaker diurnal cycle compared to clouds.

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Diurnal Cycle in Different Weather Regimes and Rainfall Variability over Borneo Associated with ENSO

Journal of Climate ◽

10.1175/jcli-d-12-00178.1 ◽

2013 ◽

Vol 26 (5) ◽

pp. 1772-1790 ◽

Cited By ~ 40

Author(s):

Jian-Hua Qian ◽

Andrew W. Robertson ◽

Vincent Moron

Keyword(s):

Diurnal Cycle ◽

El Niño ◽

El Nino ◽

Southern Oscillation ◽

Rainfall Variability ◽

Austral Summer ◽

Weather Types ◽

Sea Breezes ◽

Rainfall Anomalies ◽

Dipolar Structure

Abstract The interannual variability of precipitation over the island of Borneo in association with El Niño–Southern Oscillation (ENSO) has been studied by using the Global Precipitation Climatology Centre (GPCC) gridded rain gauge precipitation, the NOAA Climate Prediction Center (CPC) Morphing Technique (CMORPH) satellite estimated precipitation, the Quick Scatterometer (QuikSCAT) satellite estimated sea winds, and the National Centers for Environmental Prediction (NCEP)–National Center for Atmospheric Research (NCAR) reanalysis data. Analysis of the GPCC precipitation shows a dipolar structure of wet southwest versus dry central and northeast in precipitation anomalies associated with El Niño over Borneo Island during the austral summer [December–February (DJF)]. By using the 0.25° and 3-hourly CMORPH precipitation, it is found that rainfall over Borneo is strongly affected by the diurnal cycle of land–sea breezes. The spatial distribution of rainfall over Borneo depends on the direction of monsoonal winds. Weather typing analysis indicates that the dipolar structure of rainfall anomalies associated with ENSO is caused by the variability in the frequency of occurrence of different weather types. Rainfall is enhanced in the coastal region where sea breezes head against off-shore synoptic-scale low-level winds (i.e., in the lee side or wake area of the island), which is referred to here as the “wake effect.” In DJF of El Niño years, the northwesterly austral summer monsoon in southern Borneo is weaker than normal over the Maritime Continent and easterly winds are more frequent than normal over Borneo, acting to enhance rainfall over the southwest coast of the island. This coastal rainfall generation mechanism in different weather types explains the dipole pattern of a wet southwest versus dry northeast in the rainfall anomalies over Borneo Island in the El Niño years.

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Evaluation of the Daylight Cycle of Model-Predicted Cloud Amount and Condensed Water Path over Europe with Observations from MSG SEVIRI

Journal of Climate ◽

10.1175/2008jcli2391.1 ◽

2009 ◽

Vol 22 (7) ◽

pp. 1749-1766 ◽

Cited By ~ 20

Author(s):

R. A. Roebeling ◽

E. van Meijgaard

Keyword(s):

Diurnal Cycle ◽

Climate Models ◽

Climate Model ◽

Cloud Amount ◽

Daily Maximum ◽

Accurate Information ◽

Water Path ◽

Cloud Properties ◽

Condensed Water ◽

The Mediterranean

Abstract The evaluation of the diurnal cycle of cloud amount (CA) and cloud condensed water path (CWP) as predicted by climate models receives relatively little attention, mostly because of the lack of observational data capturing the diurnal cycle of such quantities. The Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the geostationary Meteosat-8 satellite is the first instrument able to provide accurate information on diurnal cycles during daylight hours of cloud properties over land and ocean surfaces. This paper evaluates the daylight cycle of CA and CWP as predicted by the Regional Atmospheric Climate Model version 2 (RACMO2), using corresponding SEVIRI retrievals. The study is done for Europe using hourly cloud properties retrievals from SEVIRI during the summer months from May to September 2004. The results of this study show that SEVIRI-retrieved daylight cycles of CA and CWP provide a powerful tool for identifying climate model deficiencies. Over Europe the SEVIRI retrievals of cloud condensed water paths comprise about 80% liquid water and about 20% ice water. The daylight cycles of CA and CWP from SEVIRI show large spatial variations in their mean values and time of daily maximum and daytime-normalized amplitude. In general, RACMO2 overestimates CWP by about 30% and underestimates CA by about 20% as compared to SEVIRI. The largest amplitudes are observed in the Mediterranean and northern Africa. For the greater part of the ocean and coastal areas the time of daily maximum CWP is found during morning, whereas over land this maximum is found after local solar noon. These features are reasonably well captured by RACMO2. In the Mediterranean and continental Europe RACMO2 tends to predict maximum CWP associated with convection to occur about two hours earlier than SEVIRI indicates.

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Influence of Subseasonal Variability on the Diurnal Cycle of Precipitation on a Mountainous Island: The Case of New Caledonia

Monthly Weather Review ◽

10.1175/mwr-d-19-0177.1 ◽

2019 ◽

Vol 148 (1) ◽

pp. 333-351 ◽

Cited By ~ 2

Author(s):

Damien Specq ◽

Gilles Bellon ◽

Alexandre Peltier ◽

Jérôme Lefèvre ◽

Christophe Menkes

Keyword(s):

Diurnal Cycle ◽

Large Scale ◽

New Caledonia ◽

Austral Summer ◽

Mountain Range ◽

Wet Season ◽

Diurnal Variability ◽

Synoptic Wind ◽

Diurnal Cycle Of Precipitation ◽

Wind Regimes

Abstract The relationship between the large-scale intraseasonal variability, synoptic wind regimes, and the local daily variability of precipitation over the main island of New Caledonia (southwest tropical Pacific) is investigated with a focus on the austral summer wet season (November–April). The average diurnal cycle of precipitation over the island is characterized by a sharp afternoon maximum around 1600 local time, with significant differences between the windward east coast, the leeward west coast, and the mountain range. The afternoon peak is related to the afternoon sea-breeze circulation and to the diurnal cycle of convection over land. In general, its magnitude follows the same evolution as the daily mean. In agreement with past studies, a clear modulation of the Madden–Julian oscillation (MJO) on both the diurnal cycle of precipitation and the probability of occurrence of four robust wind regimes can be identified in the New Caledonia region during the wet season. From the evidence that there is a qualitative correspondence between the effects of both the MJO phases and the wind regimes on features in the diurnal cycle of precipitation, a simple model is proposed to inspect the MJO forcing mediated by wind regimes on the diurnal variability of rain. The complete decomposition of the MJO impact shows that the modulation of diurnal cycle by the MJO relies on complex interactions between the MJO and synoptic winds that involve both large-scale MJO convective anomalies and MJO-induced modification of wind patterns.

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