The diurnal cycle of rainfall and its regional variation over Sumatera Island, Indonesian Maritime Continent, are examined using Tropical Rainfall Measuring Mission (TRMM) satellite precipitation radar (PR) intensive rawinsonde sounding data. TRMM PR sensor can detect raindrops directly, regardless ground cloud conditions, distinguish between convective stratiform types rainfall. this area was found to have the following characteristics: 1) with a broad peak 1500 2000 LT predominates land...

During the Monsoon Asian Hydro−Atmosphere Scientific Research and Prediction Initiative (MAHASRI; 2006–16), we carried out two projects over Indonesian maritime continent (IMC), constructing Hydrometeorological Array for Intraseasonal Variation−Monsoon Automonitoring (HARIMAU; 2005–10) radar network setting up a prototype institute climate studies, Maritime Continent Center of Excellence (MCCOE; 2009–14). Here, review climatological features world's largest "regional" rainfall IMC studied in...

Diurnal and seasonal variations of raindrop size distribution (DSD) at Gadanki (GD), Singapore (SG) Kototabang (KT) are studied to elucidate characteristics DSD in the Asian monsoon region. It is found that DSDs affected by diurnal convective cycles precipitation characteristics. GD has most significant variation DSD. Clear difference rainfall between Southwest Northeast seasons considered be main cause such clear variation. KT DSD, which probably caused fact greatly ocean-land contrast...

Abstract This study analyzes data obtained by intensive observation during a pilot field campaign of the Years Maritime Continent Project (Pre-YMC) to investigate diurnal cycle precipitation in western coastal area Sumatra Island. The period (November–December 2015) is found have number similarities with statistical behavior as revealed previous studies, such afternoon over land, nighttime offshore migration zone, and dependency on Madden–Julian oscillation (MJO) phase. Composite analyses...

An extreme precipitation/flood event that occurred in the Indonesian capital of Jakarta on Java Island middle January 2013 coincided with an active phase Madden-Julian Oscillation (MJO) enhanced convective centered western Pacific. Analysis upper-air sounding data showed strong to moderate upper westerly northwesterly winds persisted over island prior and during heavy rain event, which were caused by MJO, while near surface. Meteorological radar observations indicated regular genesis...

Abstract Motivated by observational evidence of rainfall concentrations near tropical coastlines with a diurnal cycle, the annual mean precipitation amount was quantified in tropics (latitudes lower than 37°) obtained as function coastal distance and compared between land ocean sides. The data are from Tropical Rainfall Measuring Mission (TRMM). Precipitation peaks at coastline decreases rapidly over 300 km on both sides coastline. inside “coastal region” (defined <300 coastline)...

This paper describes a diurnal cycle in systematic cloud system migration observed with the GMS IR1 sensor over Sumatera (approximately 1,500 km length) from May 2001 to April 2002. Convective clouds developed mountainous areas afternoon, and migrated westward and/or eastward for several hundred kilometers (∼ 500 km) midnight morning. Westward occurred almost every month except August southernmost Island. Eastward when lower-tropospheric winds were westerly super clusters moved along...

This study describes the characteristics of cross-equatorial northerly surge (CENS), a flow that appears intermittently over equatorial region between October and April, its relationship to precipitation patterns Maritime Continent. The CENS in this was defined as area-averaged wind exceeding 5 m s-1 105°E-115°E, 5°S-EQ based on QuikSCAT sea surface data. During 10 winters from December 2000 March 2009, 62 events were extracted classified into following patterns: 11 associated with cold...

Abstract. Regional variability of raindrop size distribution (DSD) along the Equator was investigated through a network Parsivel disdrometers in Indonesia. The were installed at Kototabang (KT; 100.32° E, 0.20° S), Pontianak (PT; 109.37° 0.00° Manado (MN; 124.92° 1.55° N) and Biak (BK; 136.10° 1.18° S). It found that DSD PT has more large drops than other three sites. DSDs four sites are influenced by both oceanic continental systems, majority data matched maritime-like reported previous...

The authors investigated diurnal convection peak characteristics over the eastern Indian Ocean off island of Sumatra during different phases Madden-Julian oscillation (MJO). During MJO 2 to 3 (P2 and P3) defined by Wheeler Hendon (2004), prominent variation in was observed satellites when moderate low-level westerly winds were dominant Ocean. peaks evening, while migrations toward early morning. By using Global Positioning System around western region offshore Sumatra, a significant...

Interannual rainfall variability over northwestern Jawa, Indonesia and its relation to the Indian Ocean Dipole (IOD) El Niño-Southern Oscillation (ENSO) events were investigated using daily data for 1973-2008. IOD clearly influence interannual variation in dry season (May-October) Jawa. Drought conditions during occur conjunction with simultaneous development of positive Niño events, whereas wet tend appear negative (with or without La Niña) rather than single Niña events. During (negative)...

<title>Abstract</title> There has been a dramatic increase in flood events over the Greater Jakarta since 2019. However, little evidence found regarding type of rainfall that is responsible most to events. This study investigates physical characteristics rainfall, drop size distribution during three cases severe on 31 December 2019–1 January 2020 (Case 1), 15–16 July 2022 2), and 6–12 October 3) its surrounding regions. The characteristic analysed categorized based stratiform, convective,...

A series of 4'α-C-branched-chain pyrimidine nucleosides was synthesized from 2'-deoxycytidine or uridine. In the series, substituent at 4'α-position affected cytotoxicity against L1210 mouse leukemic cells in vitro order Me (23) > CN (22) C⋮CH (21) CHCH2 (19) Et (24) CHCHCl (20). However, uridine and cytidine derivatives with ethynyl cyano groups did not show any cytotoxicity. The antiviral activities these HSV-1, HSV-2, HIV-1 were also examined. Compounds 22 23 showed HSV-1 HSV-2 without...

Diurnal variations in atmospheric water vapor at Koto Tabang, a mountainous area of Sumatra Island, Indonesia, are studied by analyzing the GPS-derived precipitable water, radiosonde data, and surface meteorological observation data. A permanent GPS receiving station was established Tabang March 2001. Radiosonde soundings were carried out 3-h intervals to study energy cycles Maritime Continent Indonesia. distinct diurnal variation is observed. The increases during daytime, reaching its...

Monthly statistics from TRMM‐PR and LIS observations for the three years 1998 to 2000 describe large‐scale features in rainfall lightning activity during pre‐monsoon monsoon periods of Asian South American summer monsoons. Heavy (∼5–10 mm/day) one or two months before onset was widespread mainly over land. Pre‐monsoon highly convective characterized by active lightning, a high ratio rain, echo tops. After onset, contrast, intense rains also occurred ocean land, however, intensity land...

This paper presents an overview of the HARIMAU2010 campaign focusing on convective activity with diurnal rainfall meridional march (DRMM) over Jakarta, which is located northern coast Jawa Island Indonesian maritime continent (IMC), based 1-month intensive observations by a C-band Doppler radar and multi-point atmospheric sounding array conducted during 16 January–14 February 2010. The period corresponded to phase after large-scale Madden–Julian oscillation (MJO) active convections passed...

Abstract The diurnal cycle over tropical coastal waters is characterized by offshore migration of precipitation area during nighttime. This study analyzes in situ observational data collected the YMC-Sumatra 2017 field campaign around western coast Sumatra Island, Indonesia, to examine phenomenon 5–31 December 2017, when Research Vessel Mirai was deployed about 90 km off perform observation. observed only less than a half 27 days. A comparison radiosonde at vessel between days with and...

The seasonal water cycle features over the maritime continent were determined using sources from seven regions produced by global Rayleigh-type circulation model. model output was validated statistically to reproduce stable isotopes observed δ18O and δD content of precipitation at eight stations. explains Asian-Australian monsoon well demonstrates changes origin on basis three climatic patterns as a signature rainy dry season: (1) semi-annual pattern, are indicated raise vapor Indian Ocean...

Abstract Multiscale aspects of convective systems over the Indonesian Maritime Continent in convectively active phase an intraseasonal oscillation (ISO) during November 2002 are studied using Geostationary Meteorological Satellite infrared data and ground-based observational from X-band rain radar, equatorial atmosphere L-band boundary layer upper-air soundings at Koto Tabang (KT; 0.20°S, 100.32°E; 865 m above mean sea level), West Sumatera, Indonesia. In analysis period, four super cloud...

As a part of the Coupling Processes in Equatorial Atmosphere (CPEA) program, an intensive radiosonde sounding was conducted for 30 days from April 10 to May 9, 2004, coinciding with eastward phase QBO, at seven stations over Indonesian maritime-continent, including Radar (EAR) site Koto Tabang (0.2°S, 100.32°E), west Sumatra. Using profiles, we studied behavior equatorial Kelvin waves periods 10-12 and vertical wavelengths 6-7 km. The global feature wave also analyzed simultaneous CHAMP/GPS...

One-year meteorological radar observations (from November 2006 to October 2007) over a region from the west coast of central Sumatera (Sumatra) through Mentawai Strait (about 130-km width) Siberut Island were analyzed, and modulation rainfall diurnal cycle (DC) in by Madden-Julian oscillation (MJO) was studied. The DC peaked afternoon islands, nighttime/early morning between islands. Over strait, offshore (westward) migration peak distinct when MJO active phase propagating eastward Indian...

An overview of convective activity during the HARIMAU2006 campaign conducted from 26 October to 27 November 2006 was presented, focusing on differences between coastal land/sea and inactive/active phases intraseasonal variation (ISV) based observations using an X-band Doppler radar (XDR) intensive soundings at Sumatera Island. Diurnal (DV) in convections formation heavy rainband (CHeR) along Island were also examined terms diurnal land-sea migration systems.Convection ISV inactive period...

Abstract. The vertical and temporal variations of Kelvin waves the associated effects on tropical tropopause were studied using long-term (from May 2001 to October 2005) CHAMP/GPS (CHAllenging Mini satellite Payload/Global Positioning System) radio occultation (RO) measurements. periods these found be varying in between 10 15 days, with wavelengths 5–8 km. These clearly show eastward phase propagation time-longitude section tilts height altitude-longitude, displaying characteristics waves....

Abstract The large-scale distribution of precipitation and latent heating (LH) profiles in the tropics, subtropics, part midlatitudes was studied using a 9-yr dataset derived from Tropical Rainfall Measuring Mission radar observations, with emphasis on contribution warm rain. rain showed features unique those other categories outgoing longwave radiation. Warm weak over land but widely distributed oceans, especially along intertropical convergence zone (ITCZ) western subtropical oceans....