Murray-Darling Basin
29.1 Evaporation from landscape

The volumetric value for the line item for the 2010–11 year was 746,945,199 ML. The line item represents the volume of water that passes into the atmosphere across a water/air interface including evaporation from the landscape within the Murray–Darling Basin (MDB) region.  The following table presents breakdown information for the volumetric value on sustainable diversion limit (SDL) area basis.

 

Evaporation from the landscape in the MDB region for the 2010–11 year

Water resource plan area	SDL area		Jurisdiction	Volume (ML)
	Code	Name
SW19 Warrego – Paroo – Nebine	SS29	Paroo	Qld	18,837,767
	SS28	Warrego	Qld	50,388,613
	SS27	Nebine	Qld	22,324,528
SW18 Condamine–Balonne	SS26	Condamine–Balonne	Qld	74,549,854
SW17 Moonie	SS25	Moonie	Qld	11,349,265
SW16 Qld Border Rivers	SS24	Qld Border Rivers	Qld	19,330,565
SW15 NSW Border Rivers	SS23	NSW Border Rivers	NSW	17,886,219
SW11 Barwon–Darling Watercourse	SS19	Barwon–Darling Watercourse	NSW	2,095,043
SW12 NSW Intersecting Streams	SS17	NSW Intersecting Streams	NSW	70,437,836
SW14 Gwydir	SS22	Gwydir	NSW	21,235,627
SW13 Namoi	SS21	Namoi	NSW	31,704,427
SW10 Macquarie–Castlereagh	SS20	Macquarie–Castlereagh	NSW	64,313,598
Sub-total Northern Basin				404,453,341
SW9 Lachlan	SS16	Lachlan	NSW	61,696,037
SW8 Murrumbidgee	SS15	Murrumbidgee NSW	NSW	65,377,718
SW7 NSW Murray and Lower Darling	SS18	Lower Darling	NSW	62,486,585
	SS14	NSW Murray	NSW	14,975,961
SW2 Vic Murray	SS3	Kiewa	Vic	1,976,906
SW3 Northern Victoria	SS4	Ovens	Vic	7,890,870
	SS5	Broken	Vic	3,734,817
	SS6	Goulburn	Vic	15,645,514
	SS7	Campaspe	Vic	3,776,042
	SS8	Loddon	Vic	10,861,920
SW2 Vic Murray	SS2	Vic Murray	Vic	14,026,753
SW4 Wimmera–Mallee	SS9	Wimmera–Mallee	Vic	41,027,166
SW6 Eastern Mount Lofty Ranges	SS13	Eastern Mount Lofty Ranges	SA	1,794,284
SW5 SA Murray	SS11	SA Murray	SA	697,952
	SS10	SA Non-prescribed areas	SA	33,897,131
SW6 Eastern Mount Lofty Ranges	SS12	Marne–Saunders	SA	444,387
SW1 ACT	SS1	ACT	ACT	2,181,813
Sub-total Southern Basin				342,491,858
Total for the region				746,945,199

 

 

Data sources were (1) Bureau of Meteorology (the Bureau): National Climate Centre daily climate grids (rainfall, temperature and solar radiation) and Australian Hydrological Geospatial Fabric (AHGF) waterbody feature class, and (2) Commonwealth Scientific and Industrial Research Organisation (CSIRO): WaterDyn and Australian water resource assessment – landscape (AWRA-L) model parameters, and monthly climatological average radiation grid data.

The Bureau.

Evapotranspiration from the landscape was estimated based on the AWRA-L version 1.0.0 (Van Dijk 2010) model outputs.

Using climate grid data for the Murray–Darling Basin region (including precipitation, temperature and solar radiation data), AWRA-L was used to estimate the evapotranspiration depth at each grid-point within the region. Only evapotranspiration from the landscape was considered; evapotranspiration from storages, lakes, off-channel water storages and other water bodies was not included.

The average evapotranspiration depth across the MDB landscape was determined as the weighted mean of evapotranspiration occurring from the relevant grid points within the region boundary. Points were weighted upon the area they represented within the MDB landscape to remove edge effects (where the area represented was not wholly within the MDB region) and the effect of changing area represented with changing latitude. The depth of evapotranspiration was converted to a volumetric estimate by multiplying by the total area of the MDB landscape.

The gridded climate input data were subject to approximations associated with interpolating observation point data to a national grid detailed in Jones et al. (2007).

The uncertainty estimate was not quantified.

There was no comparative line item in the 2010 Account.  The relevant volume calculated for the 2009–10 year was 515,978,016 ML.