ACRIS Dust Product Update 2006-2010
Updated information to that provided in
Rangelands 2008 – Taking the pulse
Gary Bastin, ACRIS Management Unit
CSIRO, PO Box 2111, Alice Springs NT 0871
(email: Gary.Bastin@csiro.au)
This project is supported by Ninti One Limited,
through funding from the Australian Government's Caring for our Country.
The views and opinions expressed in this publication are those of the authors and do not necessarily
reflect those of the Australian Government or the Minister for Sustainability, Environment, Water,
Population and Communities.
While reasonable efforts have been made to ensure that the contents of this publication are factually
correct, the Commonwealth does not accept responsibility for the accuracy or completeness of the
contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly
through the use of, or reliance on, the contents of this publication.
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The level of dust in the air is a useful indicator of wind erosion rate, although the amount of dust
observed is influenced by several factors (actual weather conditions, soil type, vegetation type and
ground cover etc). In Australia, a Dust Storm Index (DSI) is calculated from visibility records
made by Bureau of Meteorology (BoM) observers. The DSI provides a measure of the frequency
and intensity of wind erosion activity at continental scale. It is a composite measure of the
contributions of: local dust events, moderate dust storms and severe dust storms using weightings
for each event type, based upon dust concentrations inferred from reduced visibility during each of
these event types.
ACRIS reported spatial patterns and trend in the Dust Storm Index between 1992 and 2005 in
Rangelands 2008 – Taking the pulse (Bastin et al. 2008). This reporting was based on information
provided to ACRIS in McTainsh et al. (2007). Grant McTainsh and colleagues at Griffith
University have updated their reporting for ACRIS (see McTainsh et al. 2011). Highlights from
that report are summarised here. Readers should access the complete report (i.e. McTainsh et al.
2011) for further explanation and more comprehensive information about recent dust activity.
Changed Methods
Methods for calculating DSI have changed since dust activity was last reported in Rangelands 2008
– Taking the pulse. Manual observation frequency (MOF) is now standardised such that there must
be a continuous record between 1992 and 2010 for the data from a recording station to be included.
This reduces the risk of generating erroneously high or low mean DSI values for particular areas
where a station has a discontinuous recording history. Another change (of lesser importance) is
using inverse distance weighting to spatially interpolate DSI values between recording stations.
This method affords more control over the spread of values away from data points (BoM recording
stations) than did the previously used ‘natural neighbour’ method.
Key Points
Recent change in dust activity for rangeland bioregions is presented in two ways:
(i)
By comparing mean DSI values for 1992-2005 with those for the extended 1992-2010
period.
(ii)
By comparing change for recent years where there has been dramatic change.
When interpreting DSI maps, readers should refer to the accompanying maps of manual observation
frequency (MOF) as an indicator of DSI reliability. A higher spatial density of BoM recording
ACRIS update, Results – Dust – Final Version, November 2011
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stations with a higher recording frequency provides the most reliable data for calculating DSI
values.

Mean DSI for 1992-2010 showed that the Simpson-Strzelecki Dunefields and Channel
Country bioregions were the most active wind erosion regions (Fig. 1a & 1b, numbered
regions 19 and 21). This high wind erosion zone centred on the Lake Eyre Basin extended
west into the MacDonnell Ranges (47), north into the Mitchell Grass Downs (41) and Mount
Isa Inlier (38), east and south-east into the Mulga Lands (18) and Riverina (8), and south
into the Gawler bioregion (31). Western Australia was generally less active. The most
notable change since the Rangelands 2008 – Taking the pulse report was the spread of wind
erosion eastwards in Queensland from the Mulga Lands (18) and Darling River Plains (17)
into the cropping and grazing areas around St George and Goondiwindi.

There was a significant decrease in the number of stations with a high MOF (80-100%)
between the 1992-2005 and 1992-2010 reporting periods (Fig. 2a & 2b). High MOF is now
primarily limited to coastal stations and capital cities. This rationalisation of BoM stations
is unfortunate from a wind erosion monitoring perspective, as it is degrading the DSI record.

Comparing amongst recent years, the most dramatic changes in regional DSI occurred
between 2009 and 2010 (Fig. 3, see Fig. 4 for corresponding maps of manual observation
frequency).
(i)
DSI values between 2006 and 2008 were broadly similar to those shown in Fig. 1b.
(ii)
Dust activity in 2009 was at its highest level since 1992 (Fig. 3a). The pre-existing
high erosion zone centred on the Lake Eyre Basin extended east into the western
Murray Darling Basin, increasing to an area of approximately 1 million km2. Northsouth, it extended from the Channel Country (21) to the Flinders Lofty Block (36) and
Broken Hill Complex (25). The Stony Plains (30) bounded the western extent with the
Mulga Lands (18) forming the eastern boundary. There were secondary regions of
high wind erosion in the Cobar Peneplain (24) and further east beyond the rangelands
boundary.
(iii) There were moderate DSI values in the western desert region (Gibson Desert [59],
Little Sandy Desert [63], Great Victoria Desert [32]) in 2009. These DSI values
largely resulted from spatial data interpolation as there are very few observations from
this area (Fig. 4a). Moderate DSI values in the Gulf Fall and Uplands (46) and Gulf
Coastal (72) also result from observations external to each region.
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(iv) In stark contrast, 2010 had the lowest wind erosion in the ACRIS reporting period
(Fig. 3b), and at least as far back as 1974. The only stations to record wind erosion
activity were Quilpie in the Mulga Lands (18) region of Queensland, as well as
Tibooburra and Broken Hill in NSW. Remarkably, the Birdsville meteorological
station, which had seen dust activity every year since it started operating, did not
record a single dust code (not even haze) for the entire 2010 calendar year. In WA,
the only wind erosion was recorded in the northern Murchison (65) and eastern
Carnarvon (54) region.

Vastly improved seasonal quality in eastern and central Australia between 2009 and 2010
likely contributed to reduced dust observations and associated wind erosion activity in 2010
(Fig. 5). By contrast, 2006 was a very dry year in the south eastern rangelands and may
have had a lagged effect on high wind erosion activity in 2009.
References
Bastin, G. & the ACRIS Management Committee (2008). Rangelands 2008 – Taking the Pulse.
Published on behalf of the ACRIS Management Committee by the National Land and Water
Resources Audit, Canberra. Available at:
http://www.environment.gov.au/land/rangelands/acris/index.html
McTainsh, G.H., Tews, K., Leys, J.F. and Bastin, G.N. (2007). Spatial and temporal trends in wind
erosion of Australian rangelands during 1960 to 2005 using the Dust Storm Index (DSI). Final
Report to the Australian Collaborative Rangeland Information System, October 2007. Available
at http://www.environment.gov.au/land/rangelands/acris/index.html
McTainsh, G.H., O’Loingsigh, T. and Strong, C. (2011). Update of Dust Storm Index (DSI) maps
for 2005 to 2010 and re-analysis and mapping of DSI for 1992-2005, 1992-2008 and 1992-2010
for the Australian Collaborative Rangeland Information System (ACRIS). Available at
http://www.environment.gov.au/land/rangelands/acris/index.html
ACRIS update, Results – Dust – Final Version, November 2011
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Region
(a)
(b)
1
8
17
18
19
21
22
24
25
28
29
30
31
32
33
34
36
38
39
40
41
44
45
46
47
48
50
51
52
53
54
55
56
58
59
60
63
65
66
68
71
72
73
75
76
77
79
81
82
84
IBRA name
Murray Darling Depression
Riverina
Darling Riverine Plains
Mulga Lands
Simpson Strzelecki Dunefields
Channel Country
Brigalow Belt North
Cobar Peneplain
Broken Hill Complex
Central Ranges
Finke
Stony Plains
Gawler
Great Victoria Desert
Nullarbor
Hampton
Flinders Lofty Block
Mount Isa Inlier
Gulf Plains
Cape York Peninsula
Mitchell Grass Downs
Einasleigh Uplands
Desert Uplands
Gulf Fall and Uplands
MacDonnell Ranges
Burt Plain
Sturt Plateau
Ord Victoria Plains
Victoria Bonaparte
Gascoyne
Carnarvon
Central Kimberley
Coolgardie
Dampierland
Gibson Desert
Great Sandy Desert
Little Sandy Desert
Murchison
Northern Kimberley
Pilbara
Yalgoo
Gulf Coastal
Daly Basin
Pine Creek
Brigalow Belt South
Central Arnhem
Darwin Coastal
Arnhem Coast
Arnhem Plateau
Davenport Murchison Ranges
Figure 1. Mean DSI values for the 1992-2005 (a) and 1992-2010 (b) periods. The dots show BoM
recording stations. Bioregions are mapped and numbered for the extent of the rangelands (numbers
refer to bioregion names listed to the right of the maps).
Data source: McTainsh et al. (2011). Figure compiled by the ACRIS-MU.
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Region
(a)
(b)
1
8
17
18
19
21
22
24
25
28
29
30
31
32
33
34
36
38
39
40
41
44
45
46
47
48
50
51
52
53
54
55
56
58
59
60
63
65
66
68
71
72
73
75
76
77
79
81
82
84
IBRA name
Murray Darling Depression
Riverina
Darling Riverine Plains
Mulga Lands
Simpson Strzelecki Dunefields
Channel Country
Brigalow Belt North
Cobar Peneplain
Broken Hill Complex
Central Ranges
Finke
Stony Plains
Gawler
Great Victoria Desert
Nullarbor
Hampton
Flinders Lofty Block
Mount Isa Inlier
Gulf Plains
Cape York Peninsula
Mitchell Grass Downs
Einasleigh Uplands
Desert Uplands
Gulf Fall and Uplands
MacDonnell Ranges
Burt Plain
Sturt Plateau
Ord Victoria Plains
Victoria Bonaparte
Gascoyne
Carnarvon
Central Kimberley
Coolgardie
Dampierland
Gibson Desert
Great Sandy Desert
Little Sandy Desert
Murchison
Northern Kimberley
Pilbara
Yalgoo
Gulf Coastal
Daly Basin
Pine Creek
Brigalow Belt South
Central Arnhem
Darwin Coastal
Arnhem Coast
Arnhem Plateau
Davenport Murchison Ranges
Figure 2. Manual observation frequencies for the 1992-2005 (a) and 1992-2010 (b) periods. Circles
show BoM recording stations with the size and colour of the circle representing observation frequency.
Bioregions are mapped and numbered for the extent of the rangelands (numbers refer to bioregion
names listed to the right of the maps).
Data source: McTainsh et al. (2011). Figure compiled by the ACRIS-MU.
ACRIS update, Results – Dust – Final Version, November 2011
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(a)
(b)
Figure 3. DSI values in 2009 (a) and 2010 (b). The dots show BoM recording stations. See Figure 1
for numbered bioregions.
Data source: McTainsh et al. (2011). Figure compiled by the ACRIS-MU.
ACRIS update, Results – Dust – Final Version, November 2011
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(a)
(b)
Figure 4. Manual observation frequency for 2009 (a) and 2010 (b). Circles show BoM recording
stations with the size and colour of the circle representing observation frequency. See Figure 1 for
numbered bioregions.
Data source: McTainsh et al. (2011). Figure compiled by the ACRIS-MU.
ACRIS update, Results – Dust – Final Version, November 2011
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2005
2006
2007
2008
2009
2010
Figure 5. Annual maps of spatially-averaged decile rainfall for rangeland bioregions.
Data source: Bureau of Meteorology. Maps compiled by the ACRIS-MU.
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