scholarly journals The Impact of Concave Coastline on Rainfall Offshore Distribution over Indonesian Maritime Continent

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Furqon Alfahmi ◽  
Rizaldi Boer ◽  
Rahmat Hidayat ◽  
Perdinan ◽  
Ardhasena Sopaheluwakan

Indonesian Maritime Continent has the second longest coastline in the world, but the characteristics of offshore rainfall and its relation to coastline type are not clearly understood. As a region with eighty percent being an ocean, knowledge of offshore rainfall is important to support activity over oceans. This study investigates the climatology of offshore rainfall based on TRMM 3B42 composite during 1998-2015 and its dynamical atmosphere which induces high rainfall intensity using WRF-ARW. The result shows that concave coastline drives the increasing rainfall over ocean with Cenderawasih Bay (widest concave coastline) having the highest rainfall offshore intensity (16.5 mm per day) over Indonesian Maritime Continent. Monthly peak offshore rainfall over concave coastline is related to direction of concave coastline and peak of diurnal cycle influenced by the shifting of low level convergence. Concave coastline facing the north has peak during northwesterly monsoonal flow (March), while concave coastline facing the east has peak during easterly monsoonal flow (July). Low level convergence zone shifts from inland during daytime to ocean during nighttime. Due to shape of concave coastline, land breeze strengthens low level convergence and supports merging rainfall over ocean during nighttime. Rainfall propagating from the area around inland to ocean is approximately 5.4 m/s over Cenderawasih Bay and 4.1 m/s over Tolo Bay. Merger rainfall and low level convergence are playing role in increasing offshore rainfall over concave coastline.

Author(s):  
Jaroslav Tir ◽  
Johannes Karreth

Civil wars are one of the most pressing problems facing the world. Common approaches such as mediation, intervention, and peacekeeping have produced some results in managing ongoing civil wars, but they fall short in preventing civil wars in the first place. This book argues for considering civil wars from a developmental perspective to identify steps to assure that nascent, low-level armed conflicts do not escalate to full-scale civil wars. We show that highly structured intergovernmental organizations (IGOs, e.g. the World Bank or IMF) are particularly well positioned to engage in civil war prevention. Such organizations have both an enduring self-interest in member-state peace and stability and potent (economic) tools to incentivize peaceful conflict resolution. The book advances the hypothesis that countries that belong to a larger number of highly structured IGOs face a significantly lower risk that emerging low-level armed conflicts on their territories will escalate to full-scale civil wars. Systematic analyses of over 260 low-level armed conflicts that have occurred around the globe since World War II provide consistent and robust support for this hypothesis. The impact of a greater number of memberships in highly structured IGOs is substantial, cutting the risk of escalation by over one-half. Case evidence from Indonesia’s East Timor conflict, Ivory Coast’s post-2010 election crisis, and from the early stages of the conflict in Syria in 2011 provide additional evidence that memberships in highly structured IGOs are indeed key to understanding why some low-level armed conflicts escalate to civil wars and others do not.


Author(s):  
A.V. Goncharenko ◽  
T.O. Safonova

The article investigates the impact of Great Britain on the evolution of colonialism in the late ХІХ and early ХХ centuries. It is analyzed the sources and scientific literature on the policy of the United Kingdom in the colonial question in the late ХІХ – early ХХ century. The reasons, course and consequences of the intensification of British policy in the colonial problem are described. The process of formation and implementation of London’s initiatives in the colonial question during the period under study is studied. It is considered the position of Great Britain on the transformation of the colonial system in the late XIX – early XX centuries. The resettlement activity of the British and the peculiarities of their mentality, based on the idea of racial superiority and the new national messianism, led to the formation of developed resettlement colonies. The war for the independence of the North American colonies led to the formation of a new state on their territory, and the rest of the “white” colonies of Great Britain had at the turn of the XIX-XX centuries had to build a new policy of relations, taking into account the influence of the United States on them, and the general decline of economic and military-strategic influence of Britain in the world, and the militarization of other leading countries. As a result, a commonwealth is formed instead of an empire. With regard to other dependent territories, there is also a change in policy towards the liberalization of colonial rule and concessions to local elites. In the late ХІХ – early ХІХ centuries the newly industrialized powers (Germany, Italy, and Japan) sought to seize the colonies to reaffirm their new status in the world, the great colonial powers of the past (Spain, Portugal, and the Netherlands) sought to retain what remained to preserve their international prestige, and Russia sought to expand. The largest colonial empires, Great Britain and France, were interested in maintaining the status quo. In the colonial policy of the United Kingdom, it is possible to trace a certain line related to attempts to preserve the situation in their remote possessions and not to get involved in conflicts and costly measures where this can be avoided. In this sense, the British government showed some flexibility and foresight – the relative weakening of the military and economic power of the empire due to the emergence of new states, as well as the achievement of certain self-sufficiency, made it necessary to reconsider traditional foreign policy. Colonies are increasingly no longer seen as personal acquisitions of states, and policy toward these territories is increasingly seen as a common deal of the international community and even its moral duty. The key role here was to be played by Great Britain, which was one of the first to form the foundations of a “neocolonial” system that presupposes a solidarity policy of Western countries towards the rest of the world under the auspices of London. Colonial system in the late ХІХ – early ХІХ century underwent a major transformation, which was associated with a set of factors, the main of which were – the emergence of new industrial powers on the world stage, the internal evolution of the British Empire, changes in world trade, the emergence of new weapons, general growth of national and religious identity and related with this contradiction. The fact that the First World War did not solve many problems, such as Japanese expansionism or British marinism, and caused new ones, primarily such as the Bolshevik coup in Russia and the coming to power of the National Socialists in Germany, the implementation of the above trends stretched to later moments.


1996 ◽  
Vol 148 ◽  
pp. 1196-1223 ◽  
Author(s):  
Denis Fred Simon

There is now general agreement among observers of international economic and technology affairs that the world has entered a period characterized by the interplay of two potent and possibly dialectical forces - globalization and regionalization. Globalization, which is clearly manifested in the changing nature of competition in industries ranging from textiles to telecommunications, is being driven by a combination of diverse forces, including the communication and transportation revolutions, the growing trends towards liberalization, privatization and deregulation, and the rapid diffusion of technologies around the world. Multinational companies (MNCs) have become the principal purveyors of globalization as they seek out new markets and search the world for access to critical R D, production and distribution assets irrespective of where they may be found. Regionalization, on the other hand, has primarily been driven by macro-political forces, with governments as the initiating agents, as in die case of the formation of the European Union and the North American Free Trade Association. Where regionalization is driven by explicit and overt government actions and policies it can more often than not be seen as an anathema to globalization; politicallyinduced regionalization in these cases is driven, in large part, by concerns about loss of national competitiveness and a decline in economic welfare.


1997 ◽  
Vol 1997 (1) ◽  
pp. 409-413 ◽  
Author(s):  
Michael J. Mulhare ◽  
Paula-Jean Therrien

ABSTRACT Contamination of beach sand from two large releases of no. 2 fuel oil was found to persist for years in intertidal sand and for months in sand at the storm high tide line. This information on the unexpected persistence of this light, volatile fuel oil in the beach environment is invaluable in determining whether active remediation or natural attenuation is appropriate for the restoration of a contaminated beach. The major receptors of the impact of this contamination are a driving force in deciding what remedial approach should be taken. The two releases reported had different receptors. The major impact from the World Prodigy spill was to a public bathing beach. The oil contamination was of primary importance to residents of the town of Jamestown. Active remediation was conducted to restore an important socioeconomic resource. The major impact from the North Cape spill was to a beach in a wildlife refuge that is a protected nesting area for the threatened bird species, the piping plover. Active remediation was not conducted because of concern over disturbing the plover habitat, but would have been conducted had this been a public bathing beach.


2016 ◽  
Vol 16 (12) ◽  
pp. 7681-7693 ◽  
Author(s):  
Fanny Finger ◽  
Frank Werner ◽  
Marcus Klingebiel ◽  
André Ehrlich ◽  
Evelyn Jäkel ◽  
...  

Abstract. Spectral upward and downward solar irradiances from vertically collocated measurements above and below a cirrus layer are used to derive cirrus optical layer properties such as spectral transmissivity, absorptivity, reflectivity, and cloud top albedo. The radiation measurements are complemented by in situ cirrus crystal size distribution measurements and radiative transfer simulations based on the microphysical data. The close collocation of the radiative and microphysical measurements, above, beneath, and inside the cirrus, is accomplished by using a research aircraft (Learjet 35A) in tandem with the towed sensor platform AIRTOSS (AIRcraft TOwed Sensor Shuttle). AIRTOSS can be released from and retracted back to the research aircraft by means of a cable up to a distance of 4 km. Data were collected from two field campaigns over the North Sea and the Baltic Sea in spring and late summer 2013. One measurement flight over the North Sea proved to be exemplary, and as such the results are used to illustrate the benefits of collocated sampling. The radiative transfer simulations were applied to quantify the impact of cloud particle properties such as crystal shape, effective radius reff, and optical thickness τ on cirrus spectral optical layer properties. Furthermore, the radiative effects of low-level, liquid water (warm) clouds as frequently observed beneath the cirrus are evaluated. They may cause changes in the radiative forcing of the cirrus by a factor of 2. When low-level clouds below the cirrus are not taken into account, the radiative cooling effect (caused by reflection of solar radiation) due to the cirrus in the solar (shortwave) spectral range is significantly overestimated.


2008 ◽  
Vol 86 (1) ◽  
pp. 80-82
Author(s):  
Aldemaro Romero ◽  
Shelly Kannada

The second reply by J.W. Higdon (2008. Can. J. Zool. 86: 76–79) criticizes a previously published comment by us of T. Rastogi et al.’s (2004. Can. J. Zool. 82: 1647–1654) paper saying that we presented factual errors, misused key sources, and made a number of omissions. The main objective of our original comment was to show that there had been many other peoples and nations besides the Basques who were engaged in whaling in the North Atlantic for many centuries and, therefore, the Basques could not have been solely responsible for anthropogenic impacts on the populations of large whales in that part of the world. To that end we only sampled some sources to make our point. In this rebuttal, we show that Higdon mischaracterizes our comment as a historical review and that neither he nor B.A. McLeod et al. (2006. Can. J. Zool. 84: 1066–1069) provide any evidence that challenges our fundamental conclusions.


2020 ◽  
Author(s):  
Nicolas Blanchard ◽  
Florian Pantillon ◽  
Jean-Pierre Chaboureau ◽  
Julien Delanoë

Abstract. Warm conveyor belts (WCBs) are warm, moist airstreams of extratropical cyclones leading to widespread clouds and heavy precipitation, where associated diabatic processes can influence midlatitude dynamics. Although WCBs are traditionally seen as continuous slantwise ascents, recent studies have emphasized the presence of embedded convection and the production of mesoscale bands of negative potential vorticity (PV), the impact of which on large-scale dynamics is still debated. Here, detailed cloud and wind measurements obtained with airborne Doppler radar provide unique information on the WCB of the Stalactite cyclone on 2 October 2016 during the North Atlantic Waveguide and Downstream Impact Experiment. The measurements are complemented by a convection-permitting simulation, enabling online Lagrangian trajectories and 3-D objects clustering. The simulation reproduces well the mesoscale structure of the cyclone shown by satellite infrared observations, while the location of trajectories rising by 150 hPa during a relatively short 12 h window matches the WCB region expected from high clouds. One third of those trajectories, categorized as fast ascents, further reach a 100 hPa (2h)−1 threshold during their ascent and follow the cyclonic flow mainly at lower levels. In agreement with radar observations, convective updrafts are found in the WCB and are characterized by moderate reflectivity values up to 20 dBz and vertical velocities above 0.3 m s−1. Updraft objects and fast ascents consistently show three main types of convection in the WCB: (i) frontal convection along the surface cold front and the western edge of the low-level jet; (ii) banded convection at about 2 km altitude along the eastern edge of the low-level jet; (iii) mid-level convection below the upper-level jet. Mesoscale PV dipoles with strong positive and negative values are located in the vicinity of convective ascents and appear to accelerate both low-level and upper-level jets. Both convective ascents and negative PV organize into structures with coherent shape, location and evolution, thus suggesting a dynamical linkage. The results show that convection embedded in WCBs occurs in a coherent and organized manner rather than as isolated cells.


2021 ◽  
Vol 149 (3) ◽  
pp. 715-731
Author(s):  
Hedanqiu Bai ◽  
Gumilang Deranadyan ◽  
Courtney Schumacher ◽  
Aaron Funk ◽  
Craig Epifanio ◽  
...  

AbstractAfternoon deep convection over the Maritime Continent islands propagates offshore in the evening to early morning hours, leading to a nocturnal rainfall maximum over the nearby ocean. This work investigates the formation of the seaward precipitation migration off western Sumatra and its intraseasonal and seasonal characteristics using BMKG C-band radar observations from Padang and ERA5 reanalysis. A total of 117 nocturnal offshore rainfall events were identified in 2018, with an average propagation speed of 4.5 m s−1 within 180 km of Sumatra. Most offshore propagation events occur when the Madden–Julian oscillation (MJO) is either weak (real-time multivariate MJO index < 1) or active over the Indian Ocean (phases 1–3), whereas very few occur when the MJO is active over the Maritime Continent and western Pacific Ocean (phases 4–6). The occurrence of offshore rainfall events also varies on the basis of the seasonal evolution of the large-scale circulation associated with the Asian–Australian monsoons, with fewer events during the monsoon seasons of December–February and June–August and more during the transition seasons of March–May and September–November. Low-level convergence, resulting from the interaction of the land breeze and background low-level westerlies, is found to be the primary driver for producing offshore convective rain propagation from the west coast of Sumatra. Stratiform rain propagation speeds are further increased by upper-level easterlies, which explains the faster migration speed of high reflective clouds observed by satellite. However, temperature anomalies associated with daytime convective latent heating over Sumatra indicate that gravity waves may also modulate the offshore environment to be conducive to seaward convection migration.


1981 ◽  
Vol 1981 (1) ◽  
pp. 731-735
Author(s):  
G. W. Childers ◽  
R. W. Landers ◽  
H. G. Aranha ◽  
A. H. Ardahl ◽  
M. S. Randolph ◽  
...  

ABSTRACT Studies were carried out to detect and quantitate 12 microbial processes occurring in sediments in the north central Gulf of Mexico, and to determine the impact of low-level concentrations of oil on these processes. Under the simulated in situ conditions employed, photosynthesis, nitrification, dentrification, nitrogen fixation, sulfate reduction, and phosphate uptake were minimal, while sulfur oxidation and catabolic carbonaceous processes (heterotrophic activity, lipolysis, proteolysis cellulolysis, and chitinolysis) were present with varying degrees of activity. Little difference in metabolic activity was detected between oil-production platform sites and corresponding control sites, among different sediment types, or among three sampling seasons, and the presence of oil at up to 200 microliter per milliliter sediment had no significant impact on reaction rates. Pure culture studies confirmed that low-level concentrations of crude oil had essentially no effect on these processes.


2011 ◽  
Vol 139 (6) ◽  
pp. 1861-1878 ◽  
Author(s):  
Maxi Boettcher ◽  
Heini Wernli

Abstract The life cycle of a North Atlantic cyclone in December 2005 that included a rapid propagation phase as a diabatic Rossby wave (DRW) is investigated by means of operational analyses and deterministic forecasts from the ECMWF. A quasigeostrophic omega diagnostic has been applied to assess the impact of upper-level forcing during the genesis, propagation, and intensification phase, respectively. The system was generated in the Gulf of Mexico as a mesoscale convective vortex (MCV) influenced by vertical motion forcing from a nearby upper-level trough. The DRW propagation phase was characterized by a shallow, low-level, diabatically produced potential vorticity (PV) anomaly that rapidly propagated along the southern border of an intense baroclinic zone. No significant upper-level forcing could be identified during this phase of the development. Eventually, explosive intensification occurred as the region of vertical motion forced by an approaching upper-level trough reached the position of the DRW. The rapid intensification of 34 hPa in 24 h led to a mature extratropical cyclone in the central North Atlantic with marked frontal structures associated with a pronounced PV tower. The performance of four operational deterministic ECMWF forecasts has been investigated for the DRW propagation and cyclone intensification. The forecasts showed a highly variable skill. Despite the fact that the DRW was initially well represented in all forecasts, two of them failed to capture the explosive intensification. By applying a DRW tracking tool, the low-level baroclinicity downstream of the DRW and the moisture supply to the south of the DRW could be identified as the key environmental parameters during DRW propagation. The subsequent cyclone intensification went wrong in two of the forecasts because of the missing interaction of the DRW and the upper-level trough. It is shown that this interaction can fail if the intensity of the DRW and/or the approaching upper-level wave are too weak, or in case of an erroneous structure of the upper-level trough leading to a phasing problem of the vertical interaction with the DRW. Therefore, the DRW intensification bears similar characteristics and forecast challenges as the extratropical reintensification of tropical cyclones.


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