TY  - JOUR
A1  - Dürig, Tobias
A1  - Gudmundsson, Magnús Tumi
A1  - Karmann, Sven
A1  - Zimanowski, Bernd
A1  - Dellino, Pierfrancesco
A1  - Rietze, Martin
A1  - Büttner, Ralf
T1  - Mass eruption rates in pulsating eruptions estimated from video analysis of the gas thrust-buoyancy transition-a case study of the 2010 eruption of Eyjafjallajökull, Iceland
JF  - Earth, Planets and Space
N2  - The 2010 eruption of Eyjafjallajokull volcano was characterized by pulsating activity. Discrete ash bursts merged at higher altitude and formed a sustained quasi-continuous eruption column. High-resolution near-field videos were recorded on 8-10 May, during the second explosive phase of the eruption, and supplemented by contemporary aerial observations. In the observed period, pulses occurred at intervals of 0.8 to 23.4 s (average, 4.2 s). On the basis of video analysis, the pulse volume and the velocity of the reversely buoyant jets that initiated each pulse were determined. The expansion history of jets was tracked until the pulses reached the height of transition from a negatively buoyant jet to a convective buoyant plume about 100 m above the vent. Based on the assumption that the density of the gas-solid mixture making up the pulse approximates that of the surrounding air at the level of transition from the jet to the plume, a mass flux ranging between 2.2 and 3.5 . 10\(^4\) kg/s was calculated. This mass eruption rate is in good agreement with results obtained with simple models relating plume height with mass discharge at the vent. Our findings indicate that near-field measurements of eruption source parameters in a pulsating eruption may prove to be an effective monitoring tool. A comparison of the observed pulses with those generated in calibrated large-scale experiments reveals very similar characteristics and suggests that the analysis of near-field sensors could in the future help to constrain the triggering mechanism of explosive eruptions.
KW  - image
KW  - dynamics
KW  - infrasound
KW  - entrainment
KW  - jets
KW  - plumes
KW  - source parameters
KW  - Eyjafjallajökull 2010
KW  - pulsating explosive eruptions
KW  - near-field monitoring
KW  - eruption rate
KW  - volcano
KW  - energy
KW  - models
KW  - explosive volcanism
KW  - mass
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138635
VL  - 67
IS  - 180
ER  - 
TY  - JOUR
A1  - Timmermans, Wim J.
A1  - van der Tol, Christiaan
A1  - Timmermans, Joris
A1  - Ucer, Murat
A1  - Chen, Xuelong
A1  - Alonso, Luis
A1  - Moreno, Jose
A1  - Carrara, Arnaud
A1  - Lopez, Ramon
A1  - Fernando de la Cruz, Tercero
A1  - Corcoles, Horacio L.
A1  - de Miguel, Eduardo
A1  - Sanchez, Jose A. G.
A1  - Perez, Irene
A1  - Belen, Perez
A1  - Munoz, Juan-Carlos J.
A1  - Skokovic, Drazen
A1  - Sobrino, Jose
A1  - Soria, Guillem
A1  - MacArthur, Alasdair
A1  - Vescovo, Loris
A1  - Reusen, Ils
A1  - Andreu, Ana
A1  - Burkart, Andreas
A1  - Cilia, Chiara
A1  - Contreras, Sergio
A1  - Corbari, Chiara
A1  - Calleja, Javier F.
A1  - Guzinski, Radoslaw
A1  - Hellmann, Christine
A1  - Herrmann, Ittai
A1  - Kerr, Gregoire
A1  - Lazar, Adina-Laura
A1  - Leutner, Benjamin
A1  - Mendiguren, Gorka
A1  - Nasilowska, Sylwia
A1  - Nieto, Hector
A1  - Pachego-Labrador, Javier
A1  - Pulanekar, Survana
A1  - Raj, Rahul
A1  - Schikling, Anke
A1  - Siegmann, Bastian
A1  - von Bueren, Stefanie
A1  - Su, Zhongbo (Bob)
T1  - An Overview of the Regional Experiments for Land-atmosphere Exchanges 2012 (REFLEX 2012) Campaign
JF  - Acta Geophysica
N2  - The REFLEX 2012 campaign was initiated as part of a training course on the organization of an airborne campaign to support advancement of the understanding of land-atmosphere interaction processes. This article describes the campaign, its objectives and observations, remote as well as in situ. The observations took place at the experimental Las Tiesas farm in an agricultural area in the south of Spain. During the period of ten days, measurements were made to capture the main processes controlling the local and regional land-atmosphere exchanges. Apart from multi-temporal, multi-directional and multi-spatial space-borne and airborne observations, measurements of the local meteorology, energy fluxes, soil temperature profiles, soil moisture profiles, surface temperature, canopy structure as well as leaf-level measurements were carried out. Additional thermo-dynamical monitoring took place at selected sites. After presenting the different types of measurements, some examples are given to illustrate the potential of the observations made.
KW  - multi scale heterogeneity
KW  - quantitative remote sensing
KW  - remote
KW  - evapotranspiration
KW  - validation
KW  - issues
KW  - energy
KW  - models
KW  - water
KW  - flux
KW  - land-atmosphere interaction
KW  - turbulence
KW  - calibration and validation
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136491
VL  - 63
IS  - 6
ER  -