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A time-lapse video showing Altocumulus clouds displaying both undulatus and lenticularis features. A lower cloud layer can be seen moving in a different direction at the beginning of the sequence. Contrails and cirrus clouds can be seen at higher levels. This video has been created from images taken by the NERC MST Radar Facility's Sky-Camera, which is located near Aberystwyth in West Wales. The images are freely available, under an Open (UK) Government License, from http://tinyurl.com/nerc-mstrf-sky-camera/ . For an explanation of the atmospheric phenomena that can be seen, download the resource available at http://cedadocs.ceda.ac.uk/1259/ .

A time-lapse video showing Cumulonimbus cloud development at sunset. Most of the first Cumulonimbus cloud is obscured by the smaller Cumulus clouds in the foreground. Its anvil is clearly visible. Three further Cumulonimbus clouds cast crepuscular rays from the light of the setting sun. Their anvils merge together. This video has been created from images taken by the NERC MST Radar Facility's Sky-Camera, which is located near Aberystwyth in West Wales. The images are freely available, under an Open (UK) Government License, from http://tinyurl.com/nerc-mstrf-sky-camera/ . For an explanation of the atmospheric phenomena that can be seen, download the resource available at http://cedadocs.ceda.ac.uk/1259/ .

A time-lapse video showing Altocumulus lenticularis clouds revealing Mountain Wave activity. Notice how the positions of the clouds remain fixed relative to the landscape. This contrasts with the lower-level (Cumulus) clouds, seen at the beginning of the sequence, which move downstream with the wind. This video has been created from images taken by the NERC MST Radar Facility's Sky-Camera, which is located near Aberystwyth in West Wales. The images are freely available, under an Open (UK) Government License, from http://tinyurl.com/nerc-mstrf-sky-camera/ . For an explanation of the atmospheric phenomena that can be seen, download the resource available at http://cedadocs.ceda.ac.uk/1259/ .

A time-lapse video showing widespread development of Cumulonimbus clouds, some of which have extensive Anvils. A variety of other cumuloform clouds can be seen. The origin of the widespread cirrus cloud seen during the second half of the sequence is probably outflow from Cumulonimbus anvils. This video has been created from images taken by the NERC MST Radar Facility's Sky-Camera, which is located near Aberystwyth in West Wales. The images are freely available, under an Open (UK) Government License, from http://tinyurl.com/nerc-mstrf-sky-camera/ . For an explanation of the atmospheric phenomena that can be seen, download the resource available at http://cedadocs.ceda.ac.uk/1259/ .

A time-lapse video showing Cumulus mediocris clouds (with occasional Cirrus clouds and contrails at a higher level). The Cumulus clouds are in a continuous state of change. Many can be seen to form and/or to evaporate within the field of view. The evaporating clouds give rise to ragged Cumulus fractus formations. This video has been created from images taken by the Sky-Camera at the National Centre for Atmospheric Science (NCAS) Capel Dewi Atmospheric Observatory (CDAO) near Aberystwyth, UK - formerly known as the Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar Facility. The images are freely available under a UK Open Government Licence from http://tinyurl.com/nerc-mstrf-sky-camera/ . For more details visit http://mst.nerc.ac.uk .

A time-lapse video showing Stratocumulus clouds that develop wave-like asperitas features. During the early part of the sequence, there appear to be layers of cloud at two distinct levels. These are lit differently by the setting sun. The asperitas features begin to appear approximately half way through the sequence. Altocumulus undulatus clouds can be seen towards the end. This video has been created from images taken by the Sky-Camera at the National Centre for Atmospheric Science (NCAS) Capel Dewi Atmospheric Observatory (CDAO) near Aberystwyth, UK - formerly known as the Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar Facility. The images are freely available under a UK Open Government Licence from http://tinyurl.com/nerc-mstrf-sky-camera/ . For more details visit http://mst.nerc.ac.uk .

A time-lapse video showing Altocumulus undulatus clouds. The cloud layer initially appears to be of Stratocumulus type, with relatively poorly-defined undulatus elements. However, the layer soon breaks up to give well-defined Altocumulus undulatus. Cirrus clouds and contrails can be seen at a higher level towards the end of the sequence. This video has been created from images taken by the Sky-Camera at the National Centre for Atmospheric Science (NCAS) Capel Dewi Atmospheric Observatory (CDAO) near Aberystwyth, UK - formerly known as the Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar Facility. The images are freely available under a UK Open Government Licence from http://tinyurl.com/nerc-mstrf-sky-camera/ . For more details visit http://mst.nerc.ac.uk .

Air Force operations are directly impacted by weather on a daily basis. Erroneous forecasts negatively impact mission readiness and consequently cost the government time, in terms of wasted man-hours, and money. Advanced forecast lead-time could make a difference to minimize loss to both USAF personnel and assets. This study examined lightning data from 64 storm events from 1995-2000 in search of unique lightning signatures indicative of tornadic activity. Overall flash rates, percentage of positive flashes, positive and negative peak currents and multiplicity for each case were separated into two categories based on tornado intensity and season of occurrence. Based on the research results, there is little evidence to support the theory that specific lightning trends emerge prior to tornadogenesis. Due to the inconsistent and unreliable nature of the results, exclusive use of this time-series technique is not recommended for use in operational forecasting. The use of conventional methods, such as radar and/or satellite, used in conjunction with cloud-to-ground lightning flash data may, however, provide insight as to how electrical and physical changes relate to the development of tornadoes within a storm. Intracloud lightning may also provide additional information on tornado development and should be included in future research projects.

A time-lapse video showing Altocumulus fluctus and Altocumulus undulatus clouds followed by Altocumulus lenticularis. The short-lived fluctus cloud feature is caused by Kelvin-Helmholtz wave activity, which is generated where the wind speed changes sharply with altitude. The initial telephoto image shows the characteristic breaking-wave pattern. This was taken (at 17:37 UTC) at the same location as the camera used to to generate the video sequence, but shows a narrower field of view. The wave activity is also revealed by the Altocumulus undulatus cloud elements, which form in parallel bands. There is evidence of mountain wave activity throughout the sequence and Altocumulus lenticularis becomes the dominant cloud type towards the end. These clouds remain stationary relative to the landscape rather moving with the wind. Occasional contrails and Cirrus clouds can be seen at a higher level (one of the contrails develops undulatus features). These remain illuminated for longer than the Altocumulus clouds as the sun sets. This video has been created from images taken by the Sky-Camera at the National Centre for Atmospheric Science (NCAS) Capel Dewi Atmospheric Observatory (CDAO) near Aberystwyth, UK - formerly known as the Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar Facility. The images are freely available under a UK Open Government Licence from http://tinyurl.com/nerc-mstrf-sky-camera/ . For more details visit http://mst.nerc.ac.uk .

Stormchasing is the practice of following storm systems and storms in progress over land. Though a critical part of research into meteorology by providing on the ground data for comparison with remote radar, satellite and/or other mechanized sources, stormchasing has more recently become part of the journalistic and digital media landscape. Despite its importance, stormchasing media has not been studied as either a media form and industry in its own right or in regard to reception by its audience. This article will begin to redress this absence through a pilot study encompassing the analysis of stormchasing texts, industrial context(s) and audience reception.

Radio waves, which are used to transmit information electronically, are a portion of the larger spectrum of electromagnetic waves. They are used for purposes as diverse as telephone, AM and FM radio, UHF and VHF television, air and marine navigation, radar, radio astronomy, meteorology, data transmission, and electronic mail. Some uses of the spectrum entail transmitting or receiving information via satellites orbiting the planet. In order to communicate without interference at any given time, a user must have exclusive access to a frequency over a geographical area determined by the distance that the signals travel to targeted receivers.

Chapter 1 Principles of Tsunami -- chapter 2 Tsunami Generation Mechanisms -- chapter 3 Tsunami of Sumatra-Andaman Earthquake 26 December 2004 -- chapter 4 Novel Theories of Tsunami Generation Mechanisms -- chapter 5 Modification of the Earth's Rotation by 2004 Earthquake -- chapter 6 Principles of Optical Remote Sensing for Tsunami Observation -- chapter 7 Potential of Optical Remote Sensing Satellite for Monitoring Tsunami -- chapter 8 Modelling Shoreline Change Rates Due to the Tsunami Impact -- chapter 9 Modelling of Tsunami Impacts on Physical Properties of Water using MODIS Data: A Study Case of Aceh, Indonesia -- chapter 10 Genetic Algorithm for Simulation of Tsunami Impacts on Water Mass Variations using MODIS Satellite Data -- chapter 11 Three-dimensional Tsunami Wave Simulation from Quickbird Satellite Data -- chapter 12 Four-dimensional Hologram Interferometry of Tsunami Waves from Quickbird Satellite Data -- chapter 13 Principles of Synthetic Aperture Radar -- chapter 14 Detection of Internal Wave from Synthetic Aperture Radar Post Tsunami -- chapter 15 Altimeter Satellite Data Observed Tsunami Spreading -- chapter 16 Schrod̈inger Theory for Future Tsunami Forecasting in Malacca Straits, Indian Ocean, Red Sea and Nile River.

"This bibliography lists all AFCRL in-house reports, journal articles, and contractor reports issued from 1 October to 31 December 1967." ; "April 1968." ; Includes bibliographical references. ; Mode of access: Internet.

During the last 5 years, information on the regional tropospheric ozone levels over the eastern Mediterranean has become available but was confined to measurements at ground level. Here available information is expanded with measurements at two more rural ground level sites spanning 8° latitude, ozonesonde ascents, lidar observations, ship cruises, and aircraft flights. During wintertime the ozone monthly values are 1020 ppbv higher than values at other European sites, while during summertime the values are comparable. This results in regional ozone background levels in the area that are above the European Union (EU) 32 ppb/24 hours phytotoxicity limit during the entire year. Late spring lidar observations show that south and southwestern synoptic flows which are associated with Saharan dust events result in lower ozone above the planetary boundary layer (PBL) by 20-35 ppbv as compared to these during northerly flows, which transport air from continental Europe. These lidar observations along with ship measurements during July show that ozone is enhanced 1.5-2.2 times in the continental outflow, when compared to aged maritime air or air from the African continent. These results along with ozonesonde observations suggest that ozone abatement in the area is largely beyond the control of regional emissions and can be controlled only with emission reductions on a European scale. During September, measured background NO and NO2 levels between 3 and 4.5 km above sea level ranged from 1 to 221 pptv and from 102 to 580 pptv, respectively. The troposphere contains around 40-70 Dobson units of ozone during summer and around 20-30 Dobson units during winter. Copyright 2002 by the American Geophysical Union.

Mixing-Layer-Height (MLH) retrieval methods using backscattered lidar signals from a ceilometer (Jenoptik CHM-15k Nimbus) and temperature profiles from a Microwave Radiometer (MWR, HATPRO RPG) are compared in terms of their complementary capabilities and associated uncertainties. The Extended Kalman Filter (EKF) is used for MLH retrieval from backscattered lidar signals and the parcel method is used for MLH retrieval from MWR-derived potential-temperature profiles. The two principal sources of uncertainty in ceilometer-based MLH estimates are (i) incorrect layer attribution (~ hundreds of meters) and (ii) noise-induced errors (about 50 m at 3σ). MWR MLH uncertainties comprise (i) the total uncertainty in the retrieved potential temperature profile and (ii) ±0.5 K uncertainty in the surface temperature. Ceilometer-and MWR-based MLH estimates are in turn compared with reference to MLH estimates from radiosoundings. Twenty one measurement days from the HD(CP)2 Observational Prototype Experiment (HOPE) campaign at Jülich, Germany are considered. It is shown that the MWR can track the full Mixed Layer (ML) diurnal cycle (i.e., including morning and evening transitions) with height-increasing error bars. The ceilometer-EKF MLH estimates are much smaller errorbars than those from the MWR under the well-developed clear-sky ML but the ceilometer-EKF is prone to ambiguous tracking some multilayer scenarios (e.g., the residual layer). We therefore introduce the synergistic MLH retrieval approach that combines both ceilometer and MWR estimates in order to optimize the benefits of both. ; This work was supported by the Spanish Government – European Regional Development Funds under PGC2018- 094132-B-I00 project, and via European Union (EU) Funds under projects ACTRIS-IMP (GA-871115) and GA 101008004 (ATMO-ACCESS). CommSensLab-UPC is a María-de-Maeztu Excellence Unit (MDM-2016-0600) funded by the Agencia Estatal de Investigacion, Spain. Data were provided by Jülich Observatory for Cloud Evolution (JOYCE-CF), a core facility ...