Role of Averaging in Statistical Analysis of Solar Wind Data from the DSCOVR Spacecraft for the First Year of Operation

Geomagnetism and Aeronomy - The results from a statistical analysis of solar wind data obtained near the Earth’s orbit by the DSCOVR spacecraft for the period of one year starting August 2016...     

Modeling of Wave Dispersion Using Continuous Wavelet Transforms II: Wavelet-based Frequency-velocity Analysis

In this paper, we show how to estimate the phase velocities of multi-mode signals as present in 2-D shallow seismic surveys along a seismic line with the help of a method that is based on the deformation of the wavelet spectra of the seismic traces. In analogy with frequency-wavenumber (f–k) analysis, we perform “frequency-velocity” analysis using the correlations between phases of the wavelet spectra. Our method has two tuning parameters — the parameter of an analyzing wavelet and the parameter of a threshold operation. Numerical and experimental examples are presented to illustrate how the method accurately extracts the phase velocity from single- and multi-mode signals.     

Calibration/Data Assimilation Approach for Integrating GRACE Data into the WaterGAP Global Hydrology Model (WGHM) Using an Ensemble Kalman Filter: First Results

We introduce a new ensemble-based Kalman filter approach to assimilate GRACE satellite gravity data into the WaterGAP Global Hydrology Model. The approach (1) enables the use of the spatial resolution provided by GRACE by including the satellite observations as a gridded data product, (2) accounts for the complex spatial GRACE error correlation pattern by rigorous error propagation from the monthly GRACE solutions, and (3) allows us to integrate model parameter calibration and data assimilation within a unified framework. We investigate the formal contribution of GRACE observations to the Kalman filter update by analysis of the Kalman gain matrix. We then present first model runs, calibrated via data assimilation, for two different experiments: the first one assimilates GRACE basin averages of total water storage and the second one introduces gridded GRACE data at \(5^\circ\) resolution into the assimilation. We finally validate the assimilated model by running it in free mode (i.e., without adding any further GRACE information) for a period of 3 years following the assimilation phase and comparing the results to the GRACE observations available for this period.     

Crustal Thermal Structure of the Brazilian Equatorial Margin Using Fourier and Continuous Wavelet Transforms: A Comparative Analysis Based on Different Magnetic Datasets

Surveys in Geophysics - In this work, we calculated the Curie Point Depth (CPD) for the Brazilian Equatorial Margin using the Fourier and continuous wavelet (CWT) transforms considering a linear...