HARIMAU Radar-Profiler Network over the Indonesian Maritime Continent: A GEOSS Early Achievement for Hydrological Cycle and Disaster Prevention

Yamanaka, Manabu D.; Hashiguchi, Hiroyuki; Mori, Shuichi; Wu, Pei-Ming; Syamsudin, Fadli; Manik, Timbul; Hamada, Junji; Yamamoto, Masayuki; Kawashima, Masayuki; Fujiyoshi, Yasushi; Sakurai, Namiko; Ohi, Masayuki; Shirooka, Ryuichi; Katsumata, Masaki; Shibagaki, Yoshiaki; Shimomai, Toyoshi; Erlansyah, None; Setiawan, Wawan; Tejasukmana, Bambang; Djajadihardja, Y.; Anggadiredja, Jana T.

doi:10.20965/jdr.2008.p0078

Cited by 31 publications

(19 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our observations have been outlined in Yamanaka et al (2008Yamanaka et al ( , 2016 and Yamanaka (2016), and here, we give some details of the background (see also the map in Fig. 5b).…”

Section: Jepp−harimau and Satreps−mccoe Projectsmentioning

confidence: 72%

Maritime continent coastlines controlling Earth’s climate

Yamanaka

Ogino

et al. 2018

Prog Earth Planet Sci

Self Cite

View full text Add to dashboard Cite

During the Monsoon Asian Hydro−Atmosphere Scientific Research and Prediction Initiative (MAHASRI; 2006-16), we carried out two projects over the Indonesian maritime continent (IMC), constructing the Hydrometeorological Array for Intraseasonal Variation−Monsoon Automonitoring (HARIMAU; 2005-10) radar network and setting up a prototype institute for climate studies, the Maritime Continent Center of Excellence (MCCOE; 2009-14). Here, we review the climatological features of the world's largest "regional" rainfall over the IMC studied in these projects. The fundamental mode of atmospheric variability over the IMC is the diurnal cycle generated along coastlines by land−sea temperature contrast: afternoon land becomes hotter than sea by clear-sky insolation before noon, with the opposite contrast before sunrise caused by evening rainfall-induced "sprinkler"-like land cooling (different from the extratropical infrared cooling on clear nights). Thus, unlike the extratropics, the diurnal cycle over the IMC is more important in the rainy season. The intraseasonal, seasonal to annual, and interannual climate variabilities appear as amplitude modulations of the diurnal cycle. For example, in Jawa and Bali the rainy season is the southern hemispheric summer, because land heating in the clear morning and water vapor transport by afternoon sea breeze is strongest in the season of maximum insolation. During El Niño, cooler sea water surrounding the IMC makes morning maritime convection and rainfall weaker than normal. Because the diurnal cycle is almost the only mechanism generating convective clouds systematically near the equator with little cyclone activity, the local annual rainfall amount in the tropics is a steeply decreasing function of coastal distance (e-folding scale 100-300 km), and regional annual rainfall is an increasing function of "coastline density" (coastal length/land area) measured at a horizontal resolution of 100 km. The coastline density effect explains why rainfall and latent heating over the IMC are twice the global mean for an area that makes up only 4% of the Earth's surface. The diurnal cycles appearing almost synchronously over the whole IMC generate teleconnections between the IMC convection and the global climate. Thus, high-resolution (<< 100 km; << 1 day) observations and models over the IMC are essential to improve both local disaster prevention and global climate prediction.

show abstract

“…Our observations have been outlined in Yamanaka et al (2008Yamanaka et al ( , 2016 and Yamanaka (2016), and here, we give some details of the background (see also the map in Fig. 5b).…”

Section: Jepp−harimau and Satreps−mccoe Projectsmentioning

confidence: 72%

Maritime continent coastlines controlling Earth’s climate

Yamanaka

Ogino

et al. 2018

Prog Earth Planet Sci

Self Cite

View full text Add to dashboard Cite

show abstract

“…For this reason, we performed the first campaign observation of Hydrometeorological ARray for ISV-Monsoon AUtomonitoring (HARIMAU; Yamanaka et al 2008), called ''HARIMAU2006'', to investigate the characteristics of convective activity along the southwestern coastline of Sumatera Island and their interaction with the ISV, mainly using two XDRs and intensive atmospheric soundings from 26 October to 27 November 2006. This paper presents an overview of convective activity during the HARIMAU2006, focusing on the di¤er-ences between coastal land/sea and inactive/active ISV phases based on observations with the XDR and intensive soundings at Sumatera Island.…”

Section: Introductionmentioning

confidence: 99%

Convective Systems Developed along the Coastline of Sumatera Island, Indonesia, Observed with an X-band Doppler Radar during the HARIMAU2006 Campaign

Mori

Hamada

Sakurai

et al. 2011

Journal of the Meteorological Society of Japan

Self Cite

View full text Add to dashboard Cite

An overview of convective activity during the HARIMAU2006 campaign conducted from 26 October to 27 November 2006 was presented, focusing on the di¤erences between coastal land/sea and inactive/active phases of intraseasonal variation (ISV) based on observations using an X-band Doppler radar (XDR) and intensive soundings at Sumatera Island. Diurnal variation (DV) in coastal convections and formation of the coastal heavy rainband (CHeR) along Sumatera Island were also examined in terms of diurnal land-sea migration of coastal convective systems.Convection in the ISV inactive period (PP1) contained convective rain fractions nearly twice as much as stratiform rain fractions, whereas that in the ISV active period (PP2) comprised convective and stratiform elements almost equally. Vertical profiles of radar echo coverage for stratiform rain during PP2 were greater than those during PP1, especially in the lower troposphere over the sea. The radar echo coverage for convective rain over the sea during both periods was nearly double that over land from the near surface up to 6 km high.Convection was generated in the southwestern foothills of the mountain range in the early afternoon (12-15 Local Time, LT). Part of the convective system remained over the coastal land and exhibited weak reflectivity until the next morning. The other part migrated o¤shore at a speed of approximately 4 m s À1 and intensified until around 21 LT while still o¤shore. Additional convective cells also developed o¤shore in the early morning hours, independent of those that formed over land. Results suggested that the CHeR along Sumatera Island is dictated by diurnal variations in coastal convective development and consists of the following phases: 1) migration of convection away from the coastal land and its redevelopment in the late evening, and 2) additional generation of convection just o¤shore during the early morning hours.

show abstract

“…The Hydrometeorological ARay for IsvMonsoon AUtomonitoring (HARIMAU), a 5-year project under the Japan EOS Promotion Program (JEPP), has been operating since 2005 to set up a radar-profiler network over the IMC (Yamanaka et al 2008). The first intensive observation campaign was conducted in west Sumatera from October 26 to November 27, 2006 (HARI-MAU2006) using two X-band Doppler radars (XDRs) that covered the sea area o¤ the west coast of Sumatera Island, rawin sondes, and Equatorial Atmospheric Radar (EAR).…”

Section: Introductionmentioning

confidence: 99%

Case Study of an Intense Wind Event Associated with a Mesoscale Convective System in West Sumatera during the HARIMAU2006 Campaign

Kawashima

Fujiyoshi

Ohi

et al. 2011

Journal of the Meteorological Society of Japan

Self Cite

View full text Add to dashboard Cite

In this study, the processes responsible for an intense wind event that occurred in west Sumatera on November 19, 2006, during the first campaign of the Hydrometeorological ARay for Isv-Monsoon AUtomonitoring (HAR-IMAU) were investigated.Strong winds of 17 m s À1 and a sudden temperature drop of 5 K were observed at an X-band Doppler radar site associated with the passage of a convective system, and some houses were severely damaged. The convective system developed under an environment of strong low-level easterly vertical shear associated with the easterly region of an equatorial Rossby wave. The northern part of the convective system possessed qualitatively similar structures to midlatitude bow echoes, including the convex shape of the convective line, a descending rear-inflow jet positioned at its apex, and mesoscale vortices on both sides of the rear-inflow jet. The low-level wind behind the convective system formed a channel of strong easterly wind as it passed through an area of relatively low topography in the mountain range. The enhanced easterly wind was thought to contribute to the formation of the bow echo-like structure in the northern part of the convective system. This easterly rear-inflow jet was further accelerated in the convective system and descended near the leading edge, forming divergent strong winds at the surface.The sounding data that were taken after the passage of the convective system indicated that dry air appeared in the lower troposphere associated with an enhancement of the southerly component of the wind. An analysis of objective reanalysis data suggests that the southerly was probably associated with westward-propagating mixed Rossby-gravity waves with a period of approximately 5 days. It is suggested that the dry air intruded into the convective system across the back edge of the precipitation area and caused enhanced evaporative cooling, which resulted in the e¤ective downward transport of the enhanced easterly momentum.

show abstract

HARIMAU Radar-Profiler Network over the Indonesian Maritime Continent: A GEOSS Early Achievement for Hydrological Cycle and Disaster Prevention

Cited by 31 publications

References 43 publications

Maritime continent coastlines controlling Earth’s climate

Maritime continent coastlines controlling Earth’s climate

Convective Systems Developed along the Coastline of Sumatera Island, Indonesia, Observed with an X-band Doppler Radar during the HARIMAU2006 Campaign

Case Study of an Intense Wind Event Associated with a Mesoscale Convective System in West Sumatera during the HARIMAU2006 Campaign

Contact Info

Product

Resources

About