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  • We present a concurrent series of 144 monthly reanalyses of Super Dual Auroral Radar Network (SuperDARN) plasma velocity measurements, using the method of data-interpolating Empirical Orthogonal Functions (EOFs). For each monthly reanalysis, the 5-minute median values of the northern polar region''s radar-measured line-of-sight Doppler plasma velocities are binned in an equal-area grid defined in quasi-dipole latitude and quasi-dipole magnetic local time (MLT). The grid cells each have an area of approximately 110,000km2, and the grid extends to 30 degrees colatitude. Within this spatial grid, the sparse binned data are infilled to provide a measurement at every spatial and temporal location via two different EOF analysis models: one tailored to instances of low data coverage, the other tailored to higher data coverage. These two models each comprise 144 monthly sets of orthogonal modes of variability (spatial and temporal patterns), along with the timestamps of each epoch, and the spatial coordinate information of all bin locations. A companion dataset determines which of the two models should be chosen in each location for each month, in order to ensure the best accuracy of the infill solution. We also provide the temporal mean of the data in each spatial bin, which is removed prior to the EOF analysis. Collectively, the reanalysis delivers the SuperDARN data in terms of cardinal north and east vector components (in the quasi-dipole coordinate frame), without its usual extreme sparseness, for studies of ionospheric electrodynamics for the period 1997.0 to 2009.0. Funding was provided by NERC Standard grant NE/N01099X/1, titled ''Thermospheric Heating Modes and Effects on Satellites'' (THeMES) and the NERC grant NE/V002732/1, titled ''Space Weather Instrumentation, Measurement, Modelling, and Risk: Thermosphere'' (SWIMMR-T).

  • We present a reanalysis of SuperDARN plasma velocity measurements, using the method of data-interpolating Empirical Orthogonal Functions (EOFs). The northern polar region''s radar-measured line of sight Doppler velocities are binned in an equal-area grid (areas of approximately 110,000km2) in quasi-dipole latitude and quasi-dipole magnetic local time (MLT). Within this spatial grid, which extends to 30 degrees colatitude, the plasma velocity is given in terms of cardinal north and east vector components (in the quasi-dipole coordinate frame), with the median of every SuperDARN measurement in the spatial bin taken every 5 minutes. These sparse binned data are infilled to provide a measurement at every spatial and temporal location via EOF analysis, ultimately comprising a reanalysis spanning the month of February 2001. This resource provides a convenient method of using SuperDARN data without its usual extreme sparseness, for studies of ionospheric electrodynamics. The reanalysis is provided in sets of orthogonal modes of variability (spatial and temporal patterns), along with the timestamps of each epoch, and the spatial coordinate information of all bin locations. We also provide the temporal mean of the data in each spatial bin, which is removed prior to the EOF analysis. Funding was provided by NERC standard grants NE/N01099X/1 (THeMES) and NE/V002732/1 (SWIMMR-T).

  • A forecast model of the northern high-latitude ionospheric plasma motion as observed by the SuperDARN radars. The model comprises a set of regression coefficients. The user needs to specify the day-of-year and the monthly mean of the solar radio flux at 10.7 cm/2800 MHz, often called the f10.7 index. They also need to provide the value of the interplanetary magnetic field (IMF) component By and the Sun-Earth component of the solar wind velocity Vx, both in geocentric solar magnetospheric (GSM) coordinates. The regression coefficients are provided as two files, one can be used to model the north-south (NS) component of the plasma motion and the other to model the east-west (EW) component of the motion. Funding was provided by NERC standard grant numbers: NE/V002732/1, NE/N01099X/1, NE/V00283X/1, NE/V002686/1 and NE/T000937/1.