We present a comparison of the temperature and sodium layer properties observed by the ALOMAR Na lidar (69.3°N, 16.0°E) and simulated by the Whole Atmosphere Community Climate Model with specified dynamics and implemented sodium chemistry (WACCM-Na). To constrain the meteorological fields below 60 km, we use MERRA and GEOS-5. For the years 2008 to 2012, we analyse daily averages of temperature ...

High-resolution two-dimensional (2D) multichannel seismic data was acquired in 2014 from the Svyatogor Ridge, a sediment drift on the northwestern flank of the Knipovich spreading ridge. Seismic data is here processed, and together with multibeam bathymetry data and a correlation with Ocean Drilling Program (ODP) Hole 909, an interpretation of the structural and stratigraphic framework of the Svyatogor ...

The focus of this thesis is to investigate the use of synthetic aperture radar (SAR) compact polarimetry for studies of sea ice. Data obtained from quad-polarimetric SAR systems have already been studied extensively for sea ice monitoring. This thesis focuses on finding parallels to quad-polarimetric features from the compact-polarimetric data. This is achieved through the reconstruction of a pseudo ...

In the mining industry, equipment are continuously increasing in size and complexity. At the same time, the demand for available plants and continuous production has never been higher. The performance of equipment depends on the reliability and maintainability performance of the equipment along with the maintenance supportability, operational conditions, and environmental conditions. In order to ...

Degradation of pressurized topside static mud equipment is a very complex process. Inspection is a helpful tool to monitor degradation and helps reduce the number of critical failures. If it is left undetected and unchecked, it can lead to leakage resulting in accidents. To set up an effective inspection program, the concepts of Risk-Based Inspection (RBI) can be utilized. RBI helps to develop an ...

With the Norwegian government moving the ice edge farther north than ever before, opening for new areas for petroleum exploration, it will need research on how these areas can affect oil and gas operations. A sensitive environment along with the harsh Arctic climate and remote distances means that severe accidents, like blowouts, will have serious impacts and make cleanup and rescue actions to ...

Several ship detection algorithms have been developed over the years, where some of the most commonly used are the constant false alarm rate (CFAR) algorithms. There are challenges to the existing algorithms, both when it comes to processing time and difficult scene situations, such as heterogeneous ocean clutter and multiple targets. Existing algorithms that are equipped to handle situations ...

During the PHOCUS rocket campaign, on 20-22 July 2011, the observations of polar mesosphere summer echoes (PMSE) were made by three mesosphere-stratosphere-troposphere radars, operating at about 50 MHz. One radar, ESRAD is located at Esrange in Sweden, where the rocket was launched, two other radars, MAARSY and MORRO, are located 250 km north-west and 200 km north of ESRAD, respectively, on the other ...

An extreme heat wave occurred in Russia in the summer of 2010. It had serious impacts on humans and natural ecosystems, it was the strongest recorded globally in recent decades and exceeded in amplitude and spatial extent the previous hottest European summer in 2003. Earlier studies have not succeeded in comparing the magnitude of heat waves across continents and in time. This study introduces a new ...