Community-based wind erosion monitoring across Australia 1

April 2016

Dust activity Reduced from last month; average for April

Wind strength Less than March; on par with April 10 year average

Groundcover Steady over last three months

Rainfall Above average in western NSW and SA

Land management Stubble burning in full swing

Dust activity

Dust activity was reduced from last month and on par with April dust activity for the last 10 years.

Measured dust severity was low (moderate haze) with visibility reduced to between 5 and 10km. Three

separate dust events occurred in April 2016:

6 April 2016 registered at Euston, Junee, Temora, Cowra, Lake George and Wagga Wagga.

27 April 2016 only registered at Kyalite but was picked up by local DustWatchers.

29 April 2016 registered at Narrandera, Junee, Condobolin and Wagga Wagga.

Dust was predominantly from isolated paddocks that were bare in preparation for the upcoming cropping

season (red circle in Figure 3). Lake George has reduced groundcover and increased dust due to salt.

Figure 1: Hours of dust activity (number in brackets) at each DustWatch site in April 2016

Community-based wind erosion monitoring across Australia 2

Groundcover

Groundcover values remained largely unchanged from last month (see Figure 3).

East of the Darling River groundcover values are generally above 50% (green colours in Figure 2) with

the exception being parts of the Upper Darling Plains between Walgett and Moree that are still suffering

substantial rainfall deficiencies (Figure 5b) and parts of the Ivanhoe Plains between Menindee Lakes and

Ivanhoe.

Patchy areas with low groundcover (red colours in Figure 2) are showing in the cropping paddocks of the

Mallee Dunefield in north western Victoria and across the border into South Australia.

The desert areas of northern South Australia, western Queensland and north western New South Wales

have large areas below 50% groundcover. Nevertheless, some areas in the Simpson Desert, Eyre

Frome and Strzelecki Plains in South Australia and the Stuart Plains, the Diamantina Plains and the

Eromanga Lowlands in Queensland had good rainfalls (5b) and subsequent pasture growth (Figure3).

Groundcover is now greater than 50% (green colours in Figure 2).

Figure 2: Groundcover for April 2016 as determined from MODIS data.

Community-based wind erosion monitoring across Australia 3

Groundcover change

Groundcover in general is almost at the same level as in January 2016. There are two exceptions to this:

1. The Simpson Desert Plains and dune fields in South Australia and the Northern Territory and the

Stuart Plains, the Diamantina Plains and the Eromanga Lowlands in Queensland that have seen

a substantial increase in groundcover (blue circle in Figure 3) and

2. A substantial number of (isolated) paddocks in the New South Wales and Victorian Wheat /

Sheep belt reduced substantially in groundcover (red colours in Figure 3) – most likely due to

stubble burning in April 2016.

Figure 3: Groundcover change between January 2016 and April 2016 as determined from MODIS data.

Community-based wind erosion monitoring across Australia 4

Rainfall

Some good falls up to 100mm were recorded in central New South Wales and across southern Victoria

in April 2016. Inland Australia and in particular the Northern Territory, western Queensland and northern

South Australia received very little or no rain at all (Figure 4).

Figure 4: Rainfall totals for April 2016

The good falls in central New South Wales were un-usual for this time of the year and are therefore

reflected in the monthly decile map (blue colours in Figure 5a). All other falls were either average or

below average in April 2016 (white or red colours in Figure 5a). Looking at the last 3 months (Figure 5b)

most New South Wales and Victoria is now well below average rainfall.

Figure 5: Rainfall deciles for April 2016 (a) and 1 February 2016 to 30 April 2016 (b)

Community-based wind erosion monitoring across Australia 5

MODIS satellite

Fire activity increased substantially from last month as most fire districts lifted the total fire ban

(http://www.rfs.nsw.gov.au/fire-information/fdr-and-tobans) and landholders started paddock preparation

for the upcoming cropping season (Figure 6a). The number of fires was so big that even when zooming

into an area (Figure 6b) fire dots overlapped.

Smoke from fires trapped below an inversion layer in the first week of April caused health concerns in

the Wagga Wagga / Griffith area as reported in the Griffith “The Area News” newspaper on 6 April 2016

(http://www.areanews.com.au/story/3833488/smoke-sends-12-to-hospital/)

Figure 6a+6b: Active burning fires in April 2016 as determined from MODIS satellite.

Community-based wind erosion monitoring across Australia 6

Social Media There were not many dust storm images on social media in April 2016. Nevertheless Nicholas Shore from the Australian National University in Canberra sent us the great shot below:

Photo 1: Dust storm on the Hay plain 27-04-2016 – Nicholas Shore.

From the engine room

Good news – all the remaining DustWatch site maintenance and modem upgrade was completed in late

May. It was great to catch up with most DustWatch volunteers at the sites.

The DustWatch team Contact us at dustwatch@environment.nsw.gov.au

The MODIS image is courtesy of MODIS Rapid Response Project at NASA/GSFC; the fire data is courtesy of the Fire Information for Resource Management System (FIRMS) and the rainfall maps are from the Australian Bureau of Meteorology. This project would not be possible without funding from: the National Landcare Programme, Riverina, Western, Central West and Murray Local Land Services (LLS) in NSW; the NSW EPA, the Mallee and North Central CMAs in Victoria; the Eyre Peninsula and Murray Darling Basin NRMs in South Australian and in-kind contributions from Griffith University in Queensland and the Australian National University in Canberra We also thank our many DustWatch volunteers who provide observations and help maintain the instruments.

ISSN - 2206-3161 OEH 2016/0285