scholarly journals Propagating versus Nonpropagating Madden–Julian Oscillation Events

2014 ◽  
Vol 27 (1) ◽  
pp. 111-125 ◽  
Author(s):  
Daehyun Kim ◽  
Jong-Seong Kug ◽  
Adam H. Sobel
Keyword(s):  
Madden Julian Oscillation ◽  
Horizontal Advection ◽  
Advection Term ◽  
Rossby Wave Response ◽  
The Indian Ocean ◽  
The Difference ◽  
Static Energy ◽  
Sufficient Magnitude ◽  
Meridional Advection

Abstract Basinwide convective anomalies over the Indian Ocean (IO) associated with the Madden–Julian oscillation (MJO) sometimes propagate eastward and reach the west Pacific (WP), but sometimes do not. Long-term observations and reanalysis products are used to investigate the difference between the propagating and nonpropagating MJO events. IO convection onset events associated with the MJO are grouped into three categories based on the strengths of the simultaneous dry anomalies over the eastern Maritime Continent and WP. The IO convection anomaly preferentially makes eastward propagation and reaches the WP when the dry anomaly is stronger. Analysis of the column-integrated moist static energy (MSE) budget shows that horizontal advection moistens the atmosphere to the east of the positive MSE anomaly associated with the active convection over the IO and is of sufficient magnitude to explain the eastward propagation of the positive MSE anomaly. Interpretation is complicated, however, by lack of closure in the MSE budget. A residual term, of smaller but comparable magnitude to the horizontal advection, also moistens the column to the east of the positive MSE anomaly. Nonetheless, the authors decompose the horizontal advection term into contributions from different scales and find that a dominant contribution is from free-tropospheric meridional advection by the intraseasonal time scale wind anomalies. The positive meridional advection in between the convective and dry anomalies is induced by the anomalous poleward flow, which is interpreted as part of the Rossby wave response to the dry anomaly. The poleward flow advects the climatological MSE, which peaks at the equator, and moistens to the east of IO convective anomaly.

scholarly journals Comparison of Moist Static Energy and Budget between the GCM-Simulated Madden–Julian Oscillation and Observations over the Indian Ocean and Western Pacific

2013 ◽  
Vol 26 (14) ◽  
pp. 4981-4993 ◽  
Author(s):  
Xiaoqing Wu ◽  
Liping Deng
Keyword(s):  
Indian Ocean ◽  
General Circulation ◽  
Western Pacific ◽  
Striking Difference ◽  
Madden Julian Oscillation ◽  
Moist Static Energy ◽  
Horizontal Advection ◽  
Budget Analysis ◽  
The Indian Ocean ◽  
Static Energy

Abstract The moist static energy (MSE) anomalies and MSE budget associated with the Madden–Julian oscillation (MJO) simulated in the Iowa State University General Circulation Model (ISUGCM) over the Indian and Pacific Oceans are compared with observations. Different phase relationships between MJO 850-hPa zonal wind, precipitation, and surface latent heat flux are simulated over the Indian Ocean and western Pacific, which are greatly influenced by the convection closure, trigger conditions, and convective momentum transport (CMT). The moist static energy builds up from the lower troposphere 15–20 days before the peak of MJO precipitation, and reaches the maximum in the middle troposphere (500–600 hPa) near the peak of MJO precipitation. The gradual lower-tropospheric heating and moistening and the upward transport of moist static energy are important aspects of MJO events, which are documented in observational studies but poorly simulated in most GCMs. The trigger conditions for deep convection, obtained from the year-long cloud-resolving model (CRM) simulations, contribute to the striking difference between ISUGCM simulations with the original and modified convection schemes and play the major role in the improved MJO simulation in ISUGCM. Additionally, the budget analysis with the ISUGCM simulations shows the increase in MJO MSE is in phase with the horizontal advection of MSE over the western Pacific, while out of phase with the horizontal advection of MSE over the Indian Ocean. However, the NCEP analysis shows that the tendency of MJO MSE is in phase with the horizontal advection of MSE over both oceans.

DAMAGE AND RECONSTRUCTION OF LIFELINES IN PHANG NGA PROVINCE, THAILAND AFTER THE 2004 INDIAN OCEAN EARTHQUAKE AND TSUNAMI

2010 ◽  
Vol 04 (02) ◽  
pp. 83-93 ◽  
Author(s):  
SHIRO TAKADA ◽  
YASUKO KUWATA ◽  
ARUN PINTA
Keyword(s):  
Indian Ocean ◽  
Basic Concept ◽  
City Planning ◽  
The Other ◽  
Other Hand ◽  
The Indian Ocean ◽  
The Difference ◽  
Okushiri Island

The Indian Ocean earthquake and tsunami occurred in December 2004 caused destructive damage to Phang Nga Province, Thailand. We carried out two times of interview surveys about 1 and 3 years after the event to administrative bodies and lifeline companies for getting the information on lifeline damage, restoration and reconstruction situation, and summarized the basic concept of reconstruction plan of tsunami suffered towns considering lifeline restoration. On the other hand, as for the comparison of reconstruction problems, the lifelines recovery is reviewed at Aonae district in Okushiri Island after the 1993 Hokkaido-Nansei-oki earthquake. As the result, the difference of the process of reconstruction of town and lifelines has been revealed and the importance of preparing of the reconstruction plan before the event under the consideration of a long-term city planning is pointed out.

scholarly journals Zonal SST Difference as a Potential Environmental Factor Supporting the Longevity of the Madden–Julian Oscillation

2018 ◽  
Vol 31 (18) ◽  
pp. 7549-7564 ◽  
Author(s):  
Tamaki Suematsu ◽  
Hiroaki Miura
Keyword(s):  
Indian Ocean ◽  
Large Scale ◽  
Low Frequency ◽  
Western Pacific ◽  
Madden Julian Oscillation ◽  
Central Pacific ◽  
The Indian Ocean ◽  
The Difference ◽  
The Western Pacific ◽  
Sst Gradient

An environment favorable for the development of the Madden–Julian oscillation (MJO) was investigated by classifying MJO-like atmospheric patterns as MJO and regionally confined convective (RCC) events. Comparison of MJO and RCC events showed that even when preceded by a major convective suppression event, convective events did not develop into an MJO when large-scale buildup of moist static energy (MSE) was inhibited. The difference in the MSE accumulation between MJO and RCC is related to the contrasting low-frequency basic-state sea surface temperature (SST) pattern; the MJO and RCC events were associated with anomalously warm and cold low-frequency SSTs prevailing over the western to central Pacific, respectively. Differences in the SST anomaly field were absent from the intraseasonal frequency range of 20–60 days. The basic-state SST pattern associated with the MJO was characterized by a positive zonal SST gradient from the Indian Ocean to the western Pacific, which provided a long-standing condition that allowed for sufficient buildup of MSE across the Indian Ocean to the western Pacific via large-scale low-level convergence over intraseasonal and longer time scales. The results of this study suggest the importance of such a basic-state SST, with a long-lasting positive zonal SST gradient, for enhancing convection over a longer than intraseasonal time scale in realizing a complete MJO life cycle.

scholarly journals Objective Diagnostics and the Madden–Julian Oscillation. Part I: Methodology

2015 ◽  
Vol 28 (10) ◽  
pp. 4127-4140 ◽  
Author(s):  
Brandon O. Wolding ◽  
Eric D. Maloney
Keyword(s):  
Indian Ocean ◽  
Zonal Wind ◽  
Intraseasonal Variability ◽  
Geographical Location ◽  
Madden Julian Oscillation ◽  
Geographical Regions ◽  
The Indian Ocean ◽  
Upper Level ◽  
Static Energy ◽  
Index Value

Abstract Diagnostics obtained as an extension of empirical orthogonal function (EOF) analysis are shown to address many disadvantages of using EOF-based indices to assess the state of the Madden–Julian oscillation (MJO). The real-time multivariate MJO (RMM) index and the filtered MJO OLR (FMO) index are used to demonstrate these diagnostics. General characteristics of the indices, such as the geographical regions that most heavily influence each index, are assessed using the diagnostics. The diagnostics also identify how a given field, at various geographical locations, influences the index value at a given time. Termination (as defined by the RMM index) of the October 2011 MJO event that occurred during the Cooperative Indian Ocean Experiment on Intraseasonal Variability in the Year 2011 (CINDY) Dynamics of the MJO (DYNAMO) field campaign is shown to have resulted from changes in zonal wind anomalies at 200 hPa over the eastern Pacific Ocean, despite the onset of enhanced convection in the Indian Ocean and the persistence of favorable lower- and upper-level zonal wind anomalies near this region. The diagnostics objectively identify, for each specific geographical location, the index phase where the largest MJO-related anomalies in a given field are likely to be observed. This allows for the geographical variability of anomalous conditions associated with the MJO to be easily assessed throughout its life cycle. In Part II of this study, unique physical insight into the moist static energy and moisture budgets of the MJO is obtained from the application of diagnostics introduced here.

Reexamining the Moisture Mode Theories of the Madden–Julian Oscillation Based on Observational Analyses

2021 ◽  
Vol 34 (2) ◽  
pp. 839-853
Author(s):  
Feng Hu ◽  
Tim Li ◽  
Jianyun Gao ◽  
Lisheng Hao
Keyword(s):  
Boundary Layer ◽  
Positive Column ◽  
The Other ◽  
Madden Julian Oscillation ◽  
Moist Static Energy ◽  
Maritime Continent ◽  
Budget Analysis ◽  
Moisture Mode ◽  
The Difference ◽  
Static Energy

AbstractTwo existing moisture mode theories of the MJO, one emphasizing boundary layer moisture asymmetry (MA) and the other emphasizing column-integrated moist static energy (MSE) tendency asymmetry (TA), were validated with the diagnosis of observational data during 1979–2012. A total of 2343 MJO days are selected. While all these days show a clear phase leading of the boundary layer moisture, 20% of these days do not show a positive column-integrated MSE tendency in front of MJO convection (non-TA). A further MSE budget analysis indicates that the difference between the non-TA composite and the TA composite lies in the zonal extent of anomalously vertical overturning circulation in front of the MJO convection. A background mean precipitation modulation mechanism is proposed to explain the distinctive circulation responses. Dependent on the MJO location, an anomalous Gill response to the heating is greatly modulated by the seasonal mean and ENSO induced precipitation fields. Despite the negative MSE tendency in front of MJO convection in the non-TA group, the system continues moving eastward due to the effect of the boundary layer moistening, which promotes a convectively unstable stratification ahead of MJO convection. The analysis result suggests that the first type of moisture mode theories, the moisture asymmetry mechanism, appears more robust, particularly over the eastern Maritime Continent and western Pacific.

scholarly journals Updraft Buoyancy within and Moistening by Cumulonimbi prior to MJO Convective Onset in a Regional Model

2016 ◽  
Vol 73 (7) ◽  
pp. 2913-2934 ◽  
Author(s):  
Scott W. Powell
Keyword(s):  
Large Scale ◽  
Environmental Temperature ◽  
Transition Period ◽  
Regional Model ◽  
Madden Julian Oscillation ◽  
Horizontal Advection ◽  
Shallow Clouds ◽  
The Mean ◽  
The Difference ◽  
Environmental Temperatures

Abstract Processes responsible for widespread development of moderately deep cumulonimbi during a transition period before onset of two large-scale convective events associated with the Madden–Julian oscillation in late 2011 are investigated. A regional model (WRF) is capable of rapidly producing an approximately 3-day-long transition period prior to MJO convective onset similar to observed transition periods, during which moderately deep cumulonimbi were prevalent. During transition periods, evaporation in precipitating elements and horizontal advection of moisture away from the clouds in the nearby clear-air environment contributed to humidification below 400 hPa. Nonprecipitating clouds were present in the model mostly between 900 and 950 hPa and had no major impact on tropospheric moistening. Whether nonprecipitating cumuli grew into moderately deep cumulonimbi largely depended on the buoyancy of updrafts that extended into the 700–850-hPa layer. As mean environmental temperatures decreased, the mean cumulus updraft buoyancy in this layer became less negative. The start of two simulated transition periods were marked by rapid decreases in environmental temperature caused by reduction in environmental subsidence and/or increased cooling by advection or radiation. Small, widespread changes in the difference between 700- and 850-hPa environmental and updraft temperatures—on the order of 0.1 K and less than 0.4 K—had important ramifications for whether shallow clouds grew vertically into moderately deep clouds that moistened the troposphere and made it conducive to MJO convective onset.

A Problem of Long - Term Digital Preservation: Difference in Humanities and Natural Sciences

2014 ◽  
Vol 3 ◽  
pp. 183-195
Author(s):  
Elena Macevičiūtė
Keyword(s):  
Social Sciences ◽  
Digital Preservation ◽  
Dynamic Activity ◽  
Private Companies ◽  
Time Line ◽  
Digital Documents ◽  
Whole Process ◽  
The Difference ◽  
Technological Science

The article deals with the requirements and needs for long-term digital preservation in different areas of scholarly work. The concept of long-term digital preservation is introduced by comparing it to digitization and archiving concepts and defined with the emphasis on dynamic activity within a certain time line. The structure of digital preservation is presented with regard to the elements of the activity as understood in Activity Theory. The life-cycle of digitization processes forms the basis of the main processing of preserved data in preservation archival system.The author draws on the differences between humanities and social sciences on one hand and natural and technological science on the other. The empirical data characterizing the needs for digital preservation within different areas of scholarship are presented and show the difference in approaches to long-term digital preservation, as well as differences in selecting the items and implementing the projects of digital preservation. Institutions and organizations can also develop different understanding of preservation requirements for digital documents and other objects.The final part of the paper is devoted to some general problems pertaining to the longterm digital preservation with the emphasis of the responsibility for the whole process of safe-guarding the cultural and scholarly heritage for the re-use of the posterior generations. It is suggested that the longevity of the libraries in comparison with much shorter life-span of private companies strengthens the claim of memory institutions to playing the central role in the long-term digital preservation.

CSO Modelling Considering Moving Storms and Tipping Bucket Gauge Failures

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
M. Hochedlinger ◽  
W. Sprung ◽  
H. Kainz ◽  
K. König
Keyword(s):  
Hydrological Models ◽  
Rain Intensity ◽  
Hydrodynamic Models ◽  
Data Intensive ◽  
Storm Flow ◽  
Cell Velocity ◽  
Combined Sewer ◽  
Moving Direction ◽  
The Difference

The simulation of combined sewer overflow volumes and loads is important for the assessment of the overflow and overflow load to the receiving water to predict the hydraulic or the pollution impact. Hydrodynamic models are very data-intensive and time-consuming for long-term quality modelling. Hence, for long-term modelling, hydrological models are used to predict the storm flow in a fast way. However, in most cases, a constant rain intensity is used as load for the simulation, but in practice even for small catchments rain occurs in rain cells, which are not constant over the whole catchment area. This paper presents the results of quality modelling considering moving storms depending on the rain cell velocity and its moving direction. Additionally, tipping bucket gauge failures and different corrections are also taken into account. The results evidence the importance of these considerations for precipitation due the effects on overflow load and show the difference up to 28% of corrected and uncorrected data and of moving rain cells instead of constant raining intensities.

scholarly journals Soil erosion by snow gliding – a first quantification attempt in a subalpine area in Switzerland

2014 ◽  
Vol 18 (9) ◽  
pp. 3763-3775 ◽  
Author(s):  
K. Meusburger ◽  
G. Leitinger ◽  
L. Mabit ◽  
M. H. Mueller ◽  
A. Walter ◽  
...  
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Land Cover ◽  
Sediment Yield ◽  
Soil Loss ◽  
Water Erosion ◽  
Erosion Rates ◽  
The Difference ◽  
Snow Gliding

Abstract. Snow processes might be one important driver of soil erosion in Alpine grasslands and thus the unknown variable when erosion modelling is attempted. The aim of this study is to assess the importance of snow gliding as a soil erosion agent for four different land use/land cover types in a subalpine area in Switzerland. We used three different approaches to estimate soil erosion rates: sediment yield measurements in snow glide depositions, the fallout radionuclide 137Cs and modelling with the Revised Universal Soil Loss Equation (RUSLE). RUSLE permits the evaluation of soil loss by water erosion, the 137Cs method integrates soil loss due to all erosion agents involved, and the measurement of snow glide deposition sediment yield can be directly related to snow-glide-induced erosion. Further, cumulative snow glide distance was measured for the sites in the winter of 2009/2010 and modelled for the surrounding area and long-term average winter precipitation (1959–2010) with the spatial snow glide model (SSGM). Measured snow glide distance confirmed the presence of snow gliding and ranged from 2 to 189 cm, with lower values on the north-facing slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is an important information with respect to conservation planning and expected and ongoing land use changes in the Alps. Snow glide erosion estimated from the snow glide depositions was highly variable with values ranging from 0.03 to 22.9 t ha−1 yr−1 in the winter of 2012/2013. For sites affected by snow glide deposition, a mean erosion rate of 8.4 t ha−1 yr−1 was found. The difference in long-term erosion rates determined with RUSLE and 137Cs confirms the constant influence of snow-glide-induced erosion, since a large difference (lower proportion of water erosion compared to total net erosion) was observed for sites with high snow glide rates and vice versa. Moreover, the difference between RUSLE and 137Cs erosion rates was related to the measured snow glide distance (R2 = 0.64; p < 0.005) and to the snow deposition sediment yields (R2 = 0.39; p = 0.13). The SSGM reproduced the relative difference of the measured snow glide values under different land uses and land cover types. The resulting map highlighted the relevance of snow gliding for large parts of the investigated area. Based on these results, we conclude that snow gliding appears to be a crucial and non-negligible process impacting soil erosion patterns and magnitude in subalpine areas with similar topographic and climatic conditions.

scholarly journals Malpigmentation of Common Sole (Solea solea) during Metamorphosis Is Associated with Differential Synaptic-Related Gene Expression

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2273
Author(s):  
Menelaos Kavouras ◽  
Emmanouil E. Malandrakis ◽  
Ewout Blom ◽  
Kyriaki Tsilika ◽  
Theodoros Danis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nervous System ◽  
De Novo ◽  
Close Association ◽  
Ionic Channels ◽  
Long Term Potentiation ◽  
General Term ◽  
The Difference ◽  
Common Sole

In farmed flatfish, such as common sole, color disturbances are common. Dyschromia is a general term that includes the color defects on the blind and ocular sides of the fish. The purpose was to examine the difference in gene expression between normal pigmented and juveniles who present ambicoloration. The analysis was carried out with next-generation sequencing techniques and de novo assembly of the transcriptome. Transcripts that showed significant differences (FDR < 0.05) in the expression between the two groups, were related to those of zebrafish (Danio rerio), functionally identified, and classified into categories of the gene ontology. The results revealed that ambicolorated juveniles exhibit a divergent function, mainly of the central nervous system at the synaptic level, as well as the ionic channels. The close association of chromophore cells with the growth of nerve cells and the nervous system was recorded. The pathway, glutamate binding–activation of AMPA and NMDA receptors–long-term stimulation of postsynaptic potential–LTP (long term potentiation)–plasticity of synapses, appears to be affected. In addition, the development of synapses also seems to be affected by the interaction of the LGI (leucine-rich glioma inactivated) protein family with the ADAM (a disintegrin and metalloprotease) ones.

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