Assessment of Near Future Change in Hydrology of Wetlands in HGL of the ACT 2017 (2nd Ed)

Brief description

_This dataset supersedes all earlier versions of 'Assessment of Near Future Change in Hydrology of Wetlands in HGL of the ACT '. It incorporates HGL boundary and management area edits based on updated soil landscape mapping for the ACT._

The focus of this dataset is climate change impacts on hydrological parameters of wetlands in the Australian Capital Territory. It contains digital spatial data developed to assist in land management decision making in the ACT. The dataset contains an assessment of the change brought about by climate change on the groundwater, surface water and precipitation components of wetland water balances. Three selected regional climate projection ensembles from the NARCliM (NSW/ACT Regional Climate Modelling) project were used in the assessment – multimodel mean, CCCMA3.1-R2 and ECHAM5-R3. Only near-future (1990-2009 to 2020-2039) projections were considered.
Each variable was considered using annual and seasonal time periods. Field names in the dataset follow the following format:

Field name = MODEL_HYDRO VARIABLE_TIME PERIOD_VARIABLE\t
\t
MODEL
C – Consensus (NARCliM Multimodel Consensus Scenario)
W – Wetter (NARCliM CCCMA3.1-R2 Wetter Scenario)
D – Drier (NARCliM ECHAM5-R3 Drier Scenario)

HYDRO VARIABLE\t
P – Precipitation
S – Surface water
G – Groundwater

TIME PERIOD
A – Annual
S – Seasonality

VARIABLE\t
AC – Absolute change (mm)
PC – Percent change (%)
MC – Magnitude of change
C – Current seasonality
NF – Near future seasonality

Hydrogeological landscape (HGL) unit boundaries developed as part of the broader ACT Hydrogeological Landscapes (HGL) Framework project where used to constrain the outputs for this hydrological assessment in the ACT. In all, there are 25 HGL defined. A weighted mean was used to calculate values for each HGL unit based on the proportions of corresponding 10km gridded data from the NARCliM data set.

The outcomes suggest that the consensus scenario is the better outcome for wetlands, and despite an increase in annual volumes, the level of seasonal change in found in both the wetter and dryer scenarios poses a risk to wetlands. It is also important to note that the levels of annual water source increase predicted in the wetter scenario may also have negative impacts on wetlands.

Spatial resolution of this product is 1:50 000.