Abstract
Abstract. Maps of backscatter anisotropy parameters from the
European Organisation for the Exploitation of Meteorological Satellites
(EUMETSAT) Advanced Scatterometer (ASCAT), a C-band fan-beam scatterometer,
contain unique and valuable data characterising the surface and subsurface
of various cryospheric elements, including sea ice and ice sheets. The
computational expense and considerable complexity required to produce
parameter maps from the raw backscatter data inhibits the wider adoption of
ASCAT data. Here, backscatter anisotropy parameter maps gridded at a
resolution of 12.5 km per pixel are made available to the community in order
to facilitate the exploitation of these parameters for cryospheric
applications. These maps have been calculated from the EUMETSAT Level 1B
Sigma0 product acquired from ASCAT on board MetOp-A, MetOp-B and MetOp-C.
The dataset is unique in that it prioritises anisotropy characterisation
over temporal resolution and combines ASCAT data from multiple platforms.
The parameterisation chosen assumes a linear falloff of backscatter with
incidence angle and a fourth-order Fourier series parameterisation of azimuth
angle anisotropy. The product (Fraser and Cartwright, 2022) is
available at https://doi.org/10.26179/91c9-4783 presented on three timescales depending on orbital platform availability: 5 d (2007 to 2020 –
MetOp-A only – suitable for users requiring a long time series), 2 d
(2013 to 2020 – MetOp-A and MetOp-B) and 1 d resolution (2019–2020 –
MetOp -A, MetOp-B and MetOp-C – suitable for users needing both high temporal
resolution and detailed anisotropy characterisation). Datasets will be
updated annually.
Funder
Australian Government
Australian Research Council
Subject
General Earth and Planetary Sciences
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