Geoscience Letters

http://link.springer.com/journal/40562

List of Papers (Total 111)

Transmission of the electric fields to the low latitude ionosphere in the magnetosphere-ionosphere current circuit

The solar wind energy is transmitted to low latitude ionosphere in a current circuit from a dynamo in the magnetosphere to the equatorial ionosphere via the polar ionosphere. During the substorm growth phase and storm main phase, the dawn-to-dusk convection electric field is intensified by the southward interplanetary magnetic field (IMF), driving the ionospheric DP2 currents...

A new parameter of geomagnetic storms for the severity of space weather

Using the continuous Dst data available since 1957 and H component data for the Carrington space weather event of 1859, the paper shows that the mean value of Dst during the main phase of geomagnetic storms, called mean DstMP, is a unique parameter that can indicate the severity of space weather. All storms having high mean DstMP (≤−250 nT), which corresponds to high amount of...

Water shortage risk assessment using spatiotemporal flow simulation

Paddy irrigation practices in Taiwan utilize complicated water conveyance networks which draw streamflows from different tributaries. Characterizing and simulating streamflow series is thus an essential task for irrigation risk assessment and planning mitigation measures. It generally involves modeling the temporal variation and spatial correlation of streamflow data at different...

Long-term variations in the plasma sheet ion composition and substorm occurrence over 23 years

The Geotail satellite has been operating for almost two solar cycles (~23 years) since its launch in July 1992. The satellite carries the energetic particle and ion composition (EPIC) instrument that measures the energetic ion flux (9.4–212 keV/e) and enables the investigation of long-term variations of the ion composition in the plasma sheet for solar cycles 22–24. From the...

Dipolarization fronts and magnetic flux transport

Recent emphasis on dipolarization fronts (DFs) has led to the impression that DFs play a significant role in bringing magnetic flux to the inner magnetosphere during substorms. In this work, we investigate the amount of magnetic flux transport associated with DFs by examining the frozen-in field line condition (FIC) for previously reported DF events. A study of 18 DF cases shows...

Comparison of current disruption and magnetic reconnection

We examine similarities and differences between the concepts of current disruption (CD) and magnetic reconnection (MR). Both concepts have been invoked to account for explosive phenomena that involve energy transformation from magnetic field to charged particles. Similarities of these two concepts include (1) the occurrence of breakdown in magnetic connectivity, (2) magnetic...

Coupled onshore erosion and offshore sediment loading as causes of lower crust flow on the margins of South China Sea

Hot, thick continental crust is susceptible to ductile flow within the middle and lower crust where quartz controls mechanical behavior. Reconstruction of subsidence in several sedimentary basins around the South China Sea, most notably the Baiyun Sag, suggests that accelerated phases of basement subsidence are associated with phases of fast erosion onshore and deposition of...

Localized extensional tectonics in an overall reverse-faulting regime, Northeast Japan

In Northeast Japan, it has been recognized that trench-normal compressional stresses, aligned in the approximate direction of plate convergence, tend to dominate stress fields over a broad region. However, a particularly notable event was the shallow, normal-faulting earthquake swarms with a T-axis oriented in the E–W or NW–SE directions that occurred immediately after the 2011...

Evaluation of double-moment representation of ice hydrometeors in bulk microphysical parameterization: comparison between WRF numerical simulations and UND-Citation data during MC3E

The influence of double-moment representation of warm-rain and ice hydrometeors on the numerical simulations of a mesoscale convective system (MCS) over the US Southern Great Plains has been evaluated. The Weather Research and Forecasting (WRF) model is used to simulate the MCS with three different microphysical schemes, including the WRF single-moment 6-class (WSM6), WRF double...

A new view on the solar wind interaction with the Moon

Characterised by a surface bound exosphere and localised crustal magnetic fields, the Moon was considered as a passive object when solar wind interacts with it. However, the neutral particle and plasma measurements around the Moon by recent dedicated lunar missions, such as Chandrayaan-1, Kaguya, Chang’E-1, LRO, and ARTEMIS, as well as IBEX have revealed a variety of phenomena...

Benchmark analysis of forecasted seasonal temperature over different climatic areas

From a long-term perspective, an improvement of seasonal forecasting, which is often exclusively based on climatology, could provide a new capability for the management of energy resources in a time scale of just a few months. This paper regards a benchmark analysis in relation to long-term temperature forecasts over Italy in the year 2010, comparing the eni-kassandra meteo...

Probing of meteor showers at Mars during the encounter of comet C/2013 A1: predictions for the arrival of MAVEN/Mangalyaan

We have estimated (1) production rates, (2) ion and electron densities of meteor ablation and (3) ionization for different masses and velocities of meteoroids when comet C/2013 A1 crossed the orbit of Mars on 19 October, 2014 at 18:27 UT. Meteor ablations of small masses < 10−4 g have created a broad layer between altitude ~ 90 km and 110 km. The meteoroids of large masses ≥ 10−4...

Bernoulli equation and flow over a mountain

The Bernoulli equation is applied to an air parcel which originates at a low level at the inflow region, climbs adiabatically over a mountain with an increase in velocity, then descends on the lee side and forms a strong downslope wind. The parcel departs from hydrostatic equilibrium during its vertical motion. The air parcel can be noticeably cooler than the temperature...

Preceding seismic activity and slow slip events in the source area of the 2011 Mw 9.0 Tohoku-Oki earthquake: a review

The 2011 Tohoku-Oki earthquake ruptured a large area of the megathrust east of NE Japan. The earthquake’s magnitude was 9.0, substantially larger than predicted. It is important to know what occurred in the source area prior to this great megathrust earthquake to improve understanding of the nucleation processes of large earthquakes and risk assessments in subduction zones...

Current understanding of the aeronomy of Mars

This paper provides a short overview of our current understanding of the upper atmosphere/ionosphere of Mars including the escaping neutral atmosphere to space that plays a key role in the current state of the Mars upper atmosphere. The proper definition of the word “aeronomy” relates to the upper atmosphere where ionization is important. Currently there is a paucity of...

Preliminary investigation of the formation age and chemical characterization of the tropical peat in the middle Sepik Plain, northern Papua New Guinea

Seven gouge cores in the middle Sepik Plain (northern Papua New Guinea) were bored to clarify the depositional age and the chemical characteristics of the tropical peat. The weakly-acidic peat layer (3–4 m thick) is distributed around the south bank of the Blackwater Lakes. The peat layer consists mainly of sago palm and grass remains within a mineral matrix of very fine sand and...

New directions in hydro-climatic histories: observational data recovery, proxy records and the atmospheric circulation reconstructions over the earth (ACRE) initiative in Southeast Asia

The value of historic observational weather data for reconstructing long-term climate patterns and the detailed analysis of extreme weather events has long been recognized (Le Roy Ladurie, 1972; Lamb, 1977). In some regions however, observational data has not been kept regularly over time, or its preservation and archiving has not been considered a priority by governmental...

Distributions of inorganic nitrogen and biological production in the equatorial Pacific: a basin-scale model sensitivity study of nitrification

Recent evidence indicates that there is stronger nitrification in the euphotic zone than previously thought. We employ a physical-biogeochemical model to study the implications of nitrification for basin-scale distributions of nitrate, ammonium, and biological production in the equatorial Pacific. The model can faithfully reproduce observed features in nitrate distribution, with...

Geological and tectonic implications obtained from first seismic activity investigation around Lembang fault

The Lembang fault located at northern part of populated Bandung basin is the most conspicuous fault that potentially capable in generating earthquakes. The first seismic investigation around Lembang fault has been done by deploying a seismic network from May 2010 till December 2011 to estimate the seismic activities around that fault. Nine events were recorded and distributed...

Giant palaeo-landslide dammed the Yangtze river

Field evidence is presented to demonstrate that a very large landslide blocked the Jinsha River (the main stem of the Yangtze) near the present day town of Qiaojia, Yunnan Province. The discovery is significant because no persistent river-blocking landslide has been reported so far downstream in a major catchment. At the location of the landslide dam the upstream catchment area...

Development of Intensity-Duration-Frequency curves at ungauged sites: risk management under changing climate

The impact of a changing climate is already being felt on several hydrological systems both on a regional and sub-regional scale of the globe. Southeast Asia is one of the regions strongly affected by climate change. With climate change, one of the anticipated impacts is an increase in the intensity and frequency of extreme rainfall which further increase the region’s flood...

The interannual relationship between MJO activity and tropical cyclone genesis in the Indian Ocean

The present study investigated the relationship between the interannual variations of Madden-Julian Oscillation (MJO) and tropical cyclone genesis (TCG) over the Indian Ocean during the October-November-December season by conducting statistical analyses with the use of 33-year reanalysis data. Through dividing the 33-year period into the active year and the non-active year of MJO...

A post-Tohoku earthquake review of earthquake probabilities in the Southern Kanto District, Japan

The 2011 Mw 9.0 Tohoku earthquake generated an aftershock sequence that affected a large part of northern Honshu, and has given rise to widely divergent forecasts of changes in earthquake occurrence probabilities in northern Honshu. The objective of this review is to assess these forecasts as they relate to potential changes in the occurrence probabilities of damaging earthquakes...

A traveling atmospheric disturbance generated by a soil colour change in a high-resolution climate model experiment

The climate model CESM-WACCM is used to study the way a soil colour change of the eastern region of the Sahara affects the dynamics of the troposphere. The soil colour is darkened for 5 days. The difference between the perturbed model run and the control model run is used to isolate the soil colour change-induced atmospheric perturbation from random atmospheric waves which are...