9-second gridded ecological change measures for Tasmania: novel, disappearing and composite

Brief description

This collection contains AdaptNRM biodiversity change datasets and maps contextualised for Tasmania and surrounding Islands, and specifically: novel ecological environments, disappearing ecological environments, and composite ecological change datasets and maps for amphibians, reptiles, mammals, and vascular plants. The Tasmania extent of the equivalent ‘Potential degree of ecological change’ datasets are also included for completeness, although identical to the national datasets. Ecological change is derived from change in long term (30 year average) climates between the present (1990 centred) and projected future (2050 centred) under the MIROC5 and CanESM2 global climate models (RCP 8.5), scaled using Generalised Dissimilarity Modelling (GDM) of compositional turnover for four biological groups (GDMs: AMP_r2_PTS1, MAM_r2, REP_r3_v2, and VAS_v5_r11). The source GDM models are listed in related materials below (AMP_V2_R2 is the same as the model also denoted ‘AMP_r2_PTS1’; REP_V2_R3 is the same as REP_r3_v2; MAM_V1_R2 is the same as MAM_r2). The equivalent national datasets for novel and disappearing ecological environments, composite ecological change and Potential degree of ecological change are also listed in related materials below.
NOVEL ECOLOGICAL ENVIRONMENTS: this metric describes the nature of the projected 2050-centred future environmental conditions for each 9s grid cell. Using each cell of a GDM projection surface, the metric looks out to all other cells in the specified region, and records the ecological similarity of the future state of the cell to the most similar cell in the present (1990-centred). A novel ecological environment is a possible new ecological environment scaled by ecological similarity that may arise in the future but which doesn’t exist anywhere at present.
DISAPPEARING ECOLOGICAL ENVIRONMENTS: this metric describes the extent to which the long term average environmental conditions for each 9s grid cell in the present (1990-centred) will be present in a projected 2050 centred future. For each cell of a GDM, the metric looks out to all other cells in a specified region, and records the ecological similarity of the present state of the cell to the most similar cell in the future. A disappearing ecological environment is a present-day ecological environment scaled by ecological similarity that may become absent in the future.
COMPOSITE ECOLOGICAL CHANGE: this metric is a composite measure that integrates the Potential degree of ecological change with the degree to which ecological environments are becoming novel or disappearing, showing where different combinations of change may occur and how extreme that change may be.
A technical report for the project provides details about the rationale, methods and data. Further details are described in the AdaptNRM Guide “Implications of Climate Change for Biodiversity: a community-level modelling approach”, available online at: www.adaptnrm.org.
Data are provided in two forms: 1. Zipped ESRI float grids: Binary float grids (*.flt) with associated ESRI header files (*.hdr) and projection files (*.prj). 2. GeoTIFF files (*.tif). After extracting from the zip archive, these files can be imported into most GIS software packages. Component measures are provided in both ESRI float and GeoTiff formats, while composite rasters are provided in GeoTiff format.
Datasets in this series use a consistent naming convention: see the file readme_filenames.txt for a full explanation.
Readme and xml files for how to reproduce the 3-band colours in the composite measure are also provided.
Higher resolution images used in the technical report are also provided.
Lineage: A technical report detailing the methods and basic interpretation and analysis of outputs accompanies this collection (Ware C, Harwood T, Ferrier S, Williams KJ (2016) Contextual analysis of ecological change for Tasmania. A technical report prepared for NRM North Tasmania and partners. CSIRO Land and Water, Canberra, Australia). This technical report can also be accessed through this collection. Methods are broadly outlined in the AdaptNRM Guide “Implications of Climate Change for Biodiversity: a community-level modelling approach”, available online at: www.adaptnrm.org; see link via related materials).
GDM Model: GENERALISED DISSIMILARITY MODEL of compositional turnover in each biological group for continental Australia at 9 second resolution is described in separate collections – see link via related materials: AMP_V2_R2; REP_V2_R3; MAM_V1_R2; VAS_V5_R11. These models use best-available biological data extracted from the Atlas of Living Australia (ALA) in 2013, and spatial environmental predictor data compiled at 9 second resolution.
GDM-scaled environmental grids were used as the basis for pairwise cell comparisons across space and time using the highly parallel bespoke CSIRO Muru software to derive the metrics, running on a LINUX high-performance-computing cluster.
More detail of the calculations and methods are given in the technical report appendices.
Climate data (see AdaptNRM modules for details).
Models were built and projected using:
a) 9-second gridded climatology for continental Australia 1976-2005 using ANUCLIM v6.1 software for the 1990-centred baseline: Summary variables with elevation and radiative adjustment.
b) 9-second gridded climatology for continental Australia 2036-2065 CanESM2 RCP 8.5 or MIROC5 RCP 8.5 (CMIP5): Summary variables with elevation and radiative adjustment.