High resolution microscopy is heavily dependent on superb optical elements and superresolution microscopy even more so. Correcting unavoidable optical aberrations during post-processing is an elegant method to reduce the optical system’s complexity. A prime method that promises superresolution, aberration correction, and quantitative phase imaging is Fourier ptychography. This microscopy technique ...

Here we present an objective global climatology of polar lows. In order to obtain objective detection criteria, the efficacy of several parameters for separating polar lows from other cyclones has been compared. The comparison and the climatology are based on the ERA‐Interim reanalysis from 1979 ‐ 2016 and the high‐resolution Arctic System Reanalysis from 2000 ‐ 2012. The most effective parameters ...

SPID, Smoke Particle Impact Detector, is a Faraday cup detector designed to measure nanometer-sized meteoric smoke particles during rocket flights. We report measurements made with SPID during the G-Chaser student rocket campaign 13 January 2019 and describe the design of the SPID instruments. Model calculations of dust trajectories within the detector result in an effective cross section of 0.97 ...

Enhancements were observed in backscattered radar power during an ionospheric heating experiment from two distinct altitude regions in the auroral E region above Tromsø. For the experiment the EISCAT Tromsø heater was operated with O mode and X mode alternated at 4.04 MHz, close to the 3rd electron gyroharmonic. Ion-line data recorded with the EISCAT UHF radar reveal different temporal ...

Two Doppler imaging systems (DIS) or wide-field imaging Fabry-Perot interferometers (FPI), have recently been commissioned, one at the Auroral Station, Adventdalen, Longyearbyen, Svalbard, and the second at the IRF, Kiruna, Sweden. These instruments can provide wide-field (600 * 800 km) images of neutral wind flows in the upper thermosphere, by measuring the Doppler shift of the atomic oxygen forbidden ...

Measurements of height-dependent electric field (E) and neutral wind (u) are important governing parameters of the Earth's upper atmosphere, which can be used to study, for example, how auroral currents close or how energy flows between the ionized and neutral constituents. The new EISCAT 3D (E3D) incoherent scatter radar will be able to measure a three-dimensional ion velocity vector (v) at each ...

Synthetic aperture radar (SAR) is used for operational surveillance of ocean areas and oil spill detection. Oil spills are frequently detected around oil platforms due to the releases of so-called produced water (PW), which is water containing low concentrations of oil that can form surface slicks similar to other oil spills. PW releases are legal within given limits. Understanding the signatures ...

The coast of Northern Norway has for the first time been modeled using an unstructured grid. The modeling is done using two separate grids of different resolution, and the model data is compared to measurements done along the coast to verify its performance for both the fine and coarse grid. The model is a 2-D depth integrated model of tidal circulation with bottom friction. The data have been ...

The goal for this thesis is to test various Hybrid-Polarization (HP) Synthetic Aperture Radar (SAR) parameters using actual HP data, and to evaluate the validity of these parameters with respect to oil slick detection. As part of the evaluation, the impact of the system noise and incidence angle on the SAR images is discussed. It is shown that the Signal-to-Noise Ratio (SNR) of the sensor has a ...

We show that indications of spatial dispersion effects on mineral oil slicks are observed by space-borne multipolarization synthetic aperture radar. This is readily perceived by eye when correlating multipolarization synthetic aperture radar observables with the ship track of the dispersion vessel. We investigate real full-polarimetric (linear transmit/linear receive) as well as simulated and real ...