ACRIS Climate Variability Update 2005-2011

Updated information to that provided in

Rangelands 2008 – Taking the pulse

This project is supported by Ninti One Limited,

through funding from the Australian Government's Caring for our Country

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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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ACRIS Climate Variability Update 2005-2011

Updated information to that provided in

Rangelands 2008 – Taking the pulse

Gary Bastin, ACRIS Management Unit, CSIRO, PO Box 2111, Alice Springs NT 0871

Key points

In 2008, ACRIS documented changes in the rangelands at national and regional scales in the report Rangelands 2008-Taking the Pulse. That report was based on data for the period 1992 to 2005. Recent years have well illustrated the extreme climate variability that Australia experiences, with much of the continent changing from severe drought during parts of the last decade to some locations experiencing their wettest period on record. This document provides updated information on seasonal quality of bioregions across the rangelands, using data on annual (autumn to autumn) rainfall and modelled pasture growth.

‘Seasonal quality’ is the term ACRIS uses to rank the degree of climate variability from one year to the next. Seasonal quality broadly describes the relative value of recent rainfall on biological functioning. Relative value (quality) is judged with reference to the longer term record. ‘Biological functioning’ broadly means vegetation growth as a basic resource for both livestock (forage) and fauna (food, shelter).

In summary:

Rainfall was below average to average across much of the eastern and central rangelands between 2005-06 and 2007-08 (i.e. poorer seasonal quality).

Seasonal quality then improved across the eastern rangelands, based on rainfall, but remained poor in pastoral Western Australia, particularly in 2009-10.

The rangelands have experienced very good seasonal conditions over the last two years (2010-11 and 2011-12) with annual rainfalls being amongst the highest recorded for many bioregions.

Modelled pasture growth provides an alternative indicator of seasonal quality. It indicates the potential for pasture growth based on rainfall, soil quality and regional grazing pressure by livestock, feral herbivores and kangaroos. In some areas, this potential may not be realised because of past land degradation.

Modelled pasture growth generally supported the spatial and temporal patterns of seasonal quality indicated by rainfall but there were some regional differences. In particular, pasture recovery tended to lag rainfall coming out of the recent drought in the southern and eastern rangelands. Further, in several tropical northern bioregions much of the increased rainfall was less effective, indicated by smaller responses in the pasture growth index in most years.

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Published climate reviews

The Bureau of Meteorology has published annual climate summaries since 2001 (see www.bom.gov.au/climate/annual_sum/annsum.shtml). Longer term trends in climate variability are reported in the ‘State of the Climate’ series produced by CSIRO and the Bureau (available at www.csiro.au/Outcomes/Climate/Understanding/State-of-the-Climate.aspx). Key points, with respect to temperature and rainfall, from the 2012 report include:

Temperature

Each decade has been warmer than the previous decade since the 1950s. Australian annual average daily mean temperatures have increased by 0.9 oC since

1910. 2010 and 2011 were Australia’s coolest years recorded since 2001 due to two

consecutive La Nina events.

Rainfall

Southwest Western Australia has experienced long-term reductions in rainfall during the winter half of the year.

There has been a trend over recent decades towards increased spring and summer monsoonal rainfall across Australia’s north, higher-than-normal rainfall across the centre, and decreased late autumn and winter rainfall across the south.

Climate variability in the rangelands

Rainfall is the major driver of ecosystem and landscape processes in Australia’s rangelands. The amount of rain received, its timing and intensity, and any follow-up rains, all have a profound effect on the growth and composition of vegetation (see for example Figure 3.1, page 30, in Rangelands 2008 – Taking the pulse). A common pattern is for rainfall variability to produce large changes in herbage growth but minimally affect overall rangeland condition (defined broadly as the capacity of vegetation to respond to rainfall). Of course there are exceptions: serious degradation events have occurred in the past through excessive grazing pressure in drought (see examples in McKeon et al., 2004).

Rainfall variability occurs over two timeframes: (i) within year, or season-to-season variability (e.g. wet vs. dry, summer vs. winter) and (ii) between year, or year-to-year variability (e.g. dry years vs. wet years). ACRIS is more interested in longer-term climate variability as a driver of vegetation change. At broader spatial scale, we use map products to show how recent rainfall compares with the long-term record (pages 31 to 36 in Rangelands 2008 – Taking the pulse). At more local scale, such as at pastoral monitoring sites, ranked scores of ‘seasonal quality’1 are used to help identify grazing effects on recent vegetation change (examples in Rangelands 2008 – Taking the pulse and the Landscape Function and Critical Stock Forage updates at www.environment.gov.au/land/rangelands/acris/index.html).

1 ‘Seasonal quality’ reports the relative value of recent rainfall on biological functioning. Relative value (quality) is judged with reference to the longer term record. ‘Biological functioning’ broadly means vegetation growth as a basic resource for both livestock (forage) and fauna (food, shelter).

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This brief report updates, since 2005, climate variability information for the rangelands. It follows the presentation style used for reporting in Rangelands 2008 – Taking the pulse.

Seasonal quality

Yearly rainfall can broadly describe seasonal quality. To avoid splitting the northern wet season between calendar years, ACRIS uses an April-to-March rainfall year. Rainfall recorded at observing stations is interpolated to a gridded surface by the Bureau of Meteorology where grid cells are 0.5 degrees of latitude and longitude (approximately 5 km by 5 km). The interpolated data are most reliable where the density of recording stations is highest.

The driest and wettest years in the rangelands in the recent past are shown in Figure 1. Much of the central and southern rangelands received <150 mm rainfall between April 2004 and March 2005 and >500 mm for the same period in 2010-11.

Figure 1. Gridded rainfall in the rangelands for a particularly dry year (left) and very wet year (right). Lines show bioregion boundaries (IBRA v6.1).

Data source: www.bom.gov.au/jsp/awap (accessed 22 May 2012). Maps compiled by the ACRIS-MU.

Rain can fall in large amounts but not all of this is available, or useful, for plant growth. ACRIS uses deciles of annual rainfall to more usefully indicate seasonal quality. An alternative indicator of seasonal quality is modelled herbage availability, either as annual growth or total standing dry matter (TSDM). This approach has two advantages over rainfall for indicating seasonal quality:

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Rainfall1/4/2004 to 31/3/2005

Rainfall1/4/2010 to 31/3/2011

<100 mm

>1000 mm

1. It estimates how much of each rainfall event is used for pasture growth. This effectively discounts both small rainfall events that are ineffective for initiating growth and very large events where much rainfall may be lost to the pasture layer as runoff or deep percolation within the soil profile.

2. Most of the rangelands have infertile soils and in particularly wet periods, pasture growth is limited by nutrient deficiency (particularly nitrogen availability). Appropriately calibrated and validated models use soil properties to suitably limit pasture growth when soil moisture is abundant.

Pasture growth following rainfall is spatially modelled by AussieGRASS2 and those data can be expressed as total amount (e.g. kg/ha of annual growth or TSDM) or as a relative index (e.g. deciles of annual growth) to describe past seasons. The AussieGRASS estimate of pasture growth may exceed actual growth. This is particularly the case where past land degradation has reduced the composition of perennial pasture species and reduced rainfall infiltration through erosion.

Data sources and processing

Recent monthly grids of rainfall data for Australia were downloaded from the Bureau of Meteorology (www.bom.gov.au/jsp/awap) and accumulated to annual amounts for the April-March period. These grids were added to existing data extending back to 1890 (compiled for Rangelands 2008 – Taking the pulse). Data for each April-March period were spatially averaged across rangeland bioregions (IBRA v6.1). Each April-March rainfall for each bioregion was then calculated as a decile rank against the long-term record (i.e. 1890-91 to 2011-12).

The Queensland Climate Change Centre of Excellence provided AussieGRASS estimates of spatially-averaged annual growth and total standing dry matter for each rangeland bioregion between March of one year and February of the following year. These data were for the period 1890-91 to 2011-12. Bioregion TSDM data were used in Rangelands 2008 – Taking the pulse to describe seasonal quality (along with various indices of rainfall). Relatively high levels of TSDM indicate a body of carry-over feed for livestock, reduced drought risk and better ground cover. In many bioregions, it may also indicate increased risk of fire.

Here we use deciles of annual growth (calculated as for rainfall) as expected growth probably better indicates seasonal quality compared with TSDM. TSDM is dependent on carry-over from the previous year, is reduced by grazing and may also be affected by fire. The national fire record extends back to 1997 and recent years of modelled growth data may have a lower TSDM ranking than those years prior to the recent fire record. Simulated annual growth is less affected by preceding fires.

Deciles of seasonal quality

Recent deciles of seasonal quality based on either rainfall or AussieGRASS-simulated herbage growth are shown for every second year between 2005-06 and 2011-12 in Figure 2. As noted earlier, this six-year period spans some of the driest and wettest years experienced since European settlement. The two data types indicate that:

2 www.longpaddock.qld.gov.au/about/researchprojects/aussiegrass/index.html (accessed 20 June 2012)

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Figure 2. Seasonal quality indicated by deciles of annual rainfall and AussieGRASS simulated herbage growth. Lines show bioregion boundaries (IBRA v6.1). Data sources: www.bom.gov.au/jsp/awap and Qld Climate Change Centre of Excellence. Maps: ACRIS-MU.

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Deciles of rainfall1/4/2005 to 31/3/2006

AussieGRASS deciles of growth1/3/2005 to 28/2/2006

Deciles of rainfall1/4/2007 to 31/3/2008

AussieGRASS deciles of growth1/3/2007 to 29/2/2008

Deciles of rainfall1/4/2009 to 31/3/2010

AussieGRASS deciles of growth1/3/2009 to 28/2/2010

Deciles of rainfall1/4/2011 to 31/3/2012

AussieGRASS deciles of growth1/3/2011 to 29/2/2012

lowest decile

highest decile

Legend

The western half of the rangelands received well above-average rainfall between April 2005 and March 2006. Seasonal quality was average or below average in the east, particularly in the Mulga Lands and Brigalow Belt North bioregions.

The annual growth data suggest poorer seasonal quality in parts of the north-eastern rangelands for the same period. This was particularly the case for Cape York Peninsula where close to median rainfall translated to below-average growth. In the south, the Gawler bioregion (SA) also had a lower decile of growth than its corresponding rainfall.

Based on rainfall, much of central and southern Australia had average to below-average seasonal quality in 2007-08 (April to March period). Eastern, northern and western rangeland bioregions had generally well above-average rainfall.

Decile-ranked pasture growth suggests similar poor seasonal quality for bioregions in and neighbouring the Simpson Desert (Simpson Strzelecki Dunefields, Channel Country, Stony Plains, Gawler and Flinders Lofty Block). Lower rainfall did not adversely affect growth in the western deserts (Gibson, Little Sandy, Great Sandy, Great Victoria) although AussieGRASS simulation may not be well calibrated here.

Elsewhere, deciles of expected pasture growth were lower than corresponding rainfall in the Riverina and Murray Darling Depression bioregions (NSW and neighbouring SA) and in the Yalgoo and Coolgardie bioregions (south-western rangelands in WA).

Seasonal quality improved across much of the south eastern rangelands in 2009-10. Contrasting with this improvement, the Pilbara, Carnarvon and Gascoyne bioregions in WA experienced very dry conditions between April 2009 and March 2010 and this translated to much below-average growth for the similar period.

The growth data suggest that pasture recovery in parts of the southern and eastern rangelands lagged the increased rainfall. The Einasleigh Uplands, Darling Riverine Plains, Riverina, Murray Darling Depression, Broken Hill Complex, Flinders Lofty Block, Gawler and Nullarbor bioregions had lower deciles of pasture growth than rainfall.

Simulated pasture growth was much below-average in far northern Australia (Victoria Bonaparte, Daly Basin, Darwin Coastal, Pine Creek, Arnhem Plateau and Cape York Peninsula).

Rainfall was much above average throughout the rangelands between April 2011 and March 2012 (and similarly for 2010-11 apart from the Coolgardie bioregion).

High deciles of simulated pasture growth were also present between March 2011 and February 2012 apart from far northern Australia, particularly Cape York Peninsula. Two caveats accompany this assessment: (i) actual growth is likely to have been less than expected growth where past land degradation has altered pasture composition and increased runoff due to erosion and (ii) very high levels of pasture growth do not necessarily translate to improved liveweight gain due to nitrogen dilution and reduced protein in standing feed.

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Bioregion profiles of seasonal quality

Amounts of April-March rainfall spatially averaged across rangeland bioregions and their corresponding deciles are listed in Appendix 1. These data are for the period between 2000-01 and 2011-12. Similar data for modelled pasture growth between March of one year and February of the following are in Appendix 2.

These data can be plotted to profile changes in seasonal quality over time for selected bioregions. Example time traces for four bioregions (Figure 3) are illustrated in Figure 4. Note that decile 0 represents the lowest spatially-averaged value for a bioregion between 1890-91 and 2011-12. Higher deciles represent 10% blocks, e.g. decile 10 rainfall is the wettest 10% of years.

Figure 3. Location of bioregions whose time-trace profiles of decile rainfall and pasture growth are plotted in Figure 4.

The example profiles in Figure 4 show that:

Seasonal quality in the Desert Uplands was poor in the middle part of the last decade and then improved to be very good in more recent years. Ranking of seasonal quality based on either deciles of April-March rainfall or simulated pasture growth was broadly similar.

There was a similar trend in the Riverina although improvement in seasonal quality was more recent than in the Desert Uplands. As noted above, the increase in deciles of growth at the end of this reporting period slightly lagged rainfall. Overall, deciles of rainfall were a more variable indicator of seasonal quality than deciles of expected growth.

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The two indicators provide a mixed assessment of recent seasonal quality in the Coolgardie bioregion. Deciles of rainfall suggested quite variable seasonal quality with large changes from one year to the next. Deciles of pasture growth also varied from one year to the next, at times followed the same pattern as rainfall but between 2007-08 and 2008-09 were much lower.

Rainfall deciles for the Daly Basin indicated average to above-average seasonal quality since 2000-01. The rainfall record also suggested better seasonal quality than that indicated by modelled pasture growth.

Conclusion

Seasonal conditions in rangeland Australia between 2005-06 and 2011-12 varied from some of the worst experienced since European settlement to among the best. ACRIS uses deciles of rainfall and modelled herbage growth to indicate seasonal quality. Deciles of rainfall for the April-March annual periods were below average to average across much of the eastern and central rangelands between 2005-06 and 2007-08. Seasonal quality then improved across the eastern rangelands but remained poor in pastoral Western Australia, particularly in 2009-10. The rangelands have experienced very good seasonal conditions over the last two years (2010-11 and 2011-12) with rainfall being decile eight or higher in most bioregions. Deciles of expected pasture growth generally supported the spatial and temporal patterns of seasonal quality indicated by rainfall but there were some regional differences. In particular, pasture recovery tended to lag rainfall coming out of the recent drought in the southern and eastern rangelands. Deciles of pasture growth were also generally less than those of rainfall in some tropical northern bioregions.

References

Bastin, G. and ACRIS Management Committee (2008). Rangelands 2008 – Taking the pulse. Canberra. Published on behalf of the ACRIS Management Committee by the National Land and Water Resources Audit. Available at http://www.environment.gov.au/land/rangelands/acris/index.html

McKeon, G.M., Hall, W.B., Henry, B.K., Stone, G.S. and Watson, I.W. (2004). Pasture degradation and recovery in Australia’s rangelands: Learning from History. Queensland Department of Natural Resources, Mines and Energy.

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Desert Uplands Riverina

Coolgardie Daly Basin

Figure 4. Time traces of decile rainfall and decile pasture growth for selected rangeland bioregions. Graphs: ACRIS-MU.

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0

1

2

3

4

5

6

7

8

9

10

2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-01 2011-12

Deci

le o

f Apr

il-M

arch

Rai

nfal

l / TS

DM

rainfall

growth

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Appendix 1, part 1. Spatially-averaged gridded rainfall (mm) for rangeland bioregions. Rainfall is from April of one year to March of the following.

IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Arnhem Coast 1908 1083 1362 1498 1233 1157 1457 1506 1160 1390 1641 1532Arnhem Plateau 1885 1078 1284 1521 1194 1232 1843 1533 1099 1187 1724 1408Brigalow Belt North 776 417 312 481 396 392 544 1312 903 686 1135 805Brigalow Belt South 691 490 328 612 376 497 391 956 664 728 1058 842Broken Hill Complex 205 146 98 193 149 196 136 212 211 264 642 341Burt Plain 780 407 197 273 185 382 418 155 311 450 747 295Cape York Peninsula 1802 1211 1153 1246 1158 1276 1620 1767 1414 1145 1708 1530Carnarvon 169 70 117 213 172 377 49 432 275 90 553 273Central Arnhem 1538 1030 1120 1303 930 1005 1504 1582 1189 1249 1679 1128Central Kimberley 1083 848 603 961 577 1017 788 1012 1014 531 1240 968Central Ranges 423 621 123 343 190 384 235 196 216 258 534 415Channel Country 344 145 92 168 102 150 211 161 258 380 659 303Cobar Peneplain 496 286 183 328 261 364 241 569 350 493 631 559Coolgardie 288 207 207 382 188 353 244 265 350 233 251 334Daly Basin 1521 1124 933 1573 956 1318 1235 1392 1359 982 1573 1358Dampierland 907 522 569 762 415 764 718 753 864 493 1011 843Darling Riverine Plains 527 333 188 486 356 423 276 599 470 594 632 679Darwin Coastal 1913 1383 1442 1803 1263 1566 1962 2031 1625 1442 1868 1783Davenport Murchison Ranges

935 450 327 426 177 549 478 213 403 397 938 414

Desert Uplands 707 456 263 444 370 379 500 1288 1084 690 953 779Einasleigh Uplands 1077 701 474 633 578 626 866 1222 1483 777 1303 865Finke 361 476 130 206 128 215 152 141 202 254 595 310Flinders Lofty Block 266 227 138 192 204 251 189 176 216 283 516 332Gascoyne 259 220 222 265 142 443 202 418 346 120 423 360Gawler 168 224 136 139 170 188 180 133 173 216 363 216Gibson Desert 407 432 201 332 185 389 344 87 102 153 509 412Great Sandy Desert 685 392 253 467 225 455 408 149 190 325 649 460

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IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Great Victoria Desert 222 330 179 220 175 260 194 95 118 178 457 294Gulf Coastal 1863 791 1197 1196 696 1228 920 962 960 1068 1354 1082Gulf Fall and Uplands 1476 675 947 1038 545 934 820 948 1063 790 1210 899Gulf Plains 1155 656 527 690 534 850 836 1087 1356 846 1253 932Hampton 346 283 179 317 273 332 266 203 276 262 513 326Little Sandy Desert 368 389 279 360 147 408 380 151 132 123 422 409MacDonnell Ranges 717 424 178 230 175 313 294 143 312 489 885 312Mitchell Grass Downs 708 322 262 390 255 366 402 405 559 474 731 485Mount Isa Inlier 828 326 317 548 398 568 394 399 916 520 864 553Mulga Lands 421 279 123 343 212 246 267 563 376 605 639 569Murchison 262 239 187 259 179 389 211 265 250 176 372 359Murray Darling Depression 300 201 125 231 198 303 188 301 259 330 675 391Northern Kimberley 1398 786 865 1371 849 1364 1168 1481 1348 893 1802 1451Nullarbor 226 251 193 224 180 308 198 150 203 174 403 219Ord Victoria Plain 1133 633 579 834 497 869 601 820 802 505 1019 702Pilbara 439 243 278 438 122 675 359 386 462 163 460 423Pine Creek 1893 1255 1199 1588 1081 1321 1845 1619 1397 1191 1725 1667Riverina 403 260 156 311 276 339 194 346 253 385 731 477Simpson Strzelecki Dunefields

290 198 93 101 75 142 152 61 127 253 549 212

Stony Plains 164 252 115 105 107 144 104 75 145 210 442 212Sturt Plateau 1236 620 838 1022 456 928 674 863 978 621 1062 881Tanami 1005 502 278 506 175 650 481 252 352 450 826 434Tiwi Cobourg 1879 1066 1274 1206 1492 1163 1317 1292 1087 1167 1583 1522Victoria Bonaparte 1286 956 694 1303 848 1255 964 1215 1500 799 1337 1035Yalgoo 228 195 174 234 179 358 164 396 310 209 361 312

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Appendix 1, part 2. Deciles of rainfall for rangeland bioregions.

IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Arnhem Coast 10 4 8 9 6 4 9 9 5 8 10 9Arnhem Plateau 10 3 7 9 6 6 10 10 4 5 10 9Brigalow Belt North 8 3 1 4 2 2 5 10 9 7 10 8Brigalow Belt South 8 4 1 6 1 4 2 10 7 8 10 9Broken Hill Complex 7 3 1 6 4 6 2 7 7 9 10 10Burt Plain 10 9 4 6 3 9 9 2 8 9 10 7Cape York Peninsula 10 4 3 5 3 5 9 10 7 3 10 9Carnarvon 4 1 2 6 4 9 0 10 8 1 10 8Central Arnhem 10 6 7 9 3 5 10 10 8 9 10 7Central Kimberley 10 8 4 9 4 10 8 10 10 3 10 9Central Ranges 10 10 2 9 6 9 8 6 7 8 10 10Channel Country 9 4 1 5 2 4 7 4 8 10 10 9Cobar Peneplain 9 3 1 4 2 5 2 10 5 9 10 9Coolgardie 7 3 3 10 2 9 5 6 9 4 5 9Daly Basin 10 6 4 10 4 9 8 9 9 5 10 9Dampierland 10 5 6 9 3 9 8 8 10 4 10 9Darling Riverine Plains 8 3 0 8 3 6 2 9 7 9 10 10Darwin Coastal 10 5 6 9 4 8 10 10 8 6 10 9Davenport Murchison Ranges

10 8 6 8 2 9 9 2 8 7 10 8

Desert Uplands 8 5 1 5 3 3 6 10 10 8 10 9Einasleigh Uplands 9 5 1 4 3 4 8 10 10 6 10 8Finke 10 10 3 7 3 8 5 4 7 8 10 9Flinders Lofty Block 8 6 1 4 5 7 4 3 5 8 10 9Gascoyne 7 6 6 7 2 10 5 10 9 2 10 10Gawler 5 9 3 4 6 6 6 3 6 8 10 8Gibson Desert 10 10 7 9 6 10 9 1 2 5 10 10Great Sandy Desert 10 9 6 10 5 9 9 1 3 8 10 10

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IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Great Victoria Desert 8 10 6 8 6 9 7 1 2 6 10 10Gulf Coastal 10 5 10 10 4 10 8 8 8 9 10 9Gulf Fall and Uplands 10 6 9 10 3 9 8 10 10 8 10 9Gulf Plains 10 4 2 5 2 8 8 10 10 8 10 9Hampton 9 7 2 9 7 9 6 3 7 6 10 9Little Sandy Desert 9 10 8 9 4 10 10 4 3 3 10 10MacDonnell Ranges 10 9 3 5 3 8 7 2 8 10 10 8Mitchell Grass Downs 10 5 2 7 2 6 7 7 9 8 10 8Mount Isa Inlier 10 3 3 8 5 8 5 5 10 8 10 8Mulga Lands 8 4 0 6 2 3 3 9 7 10 10 10Murchison 8 7 4 8 4 10 6 8 7 4 10 10Murray Darling Depression

8 3 1 5 3 8 2 8 6 8 10 9

Northern Kimberley 10 3 4 9 4 9 8 10 9 4 10 10Nullarbor 8 9 6 8 5 10 7 3 7 5 10 7Ord Victoria Plain 10 8 7 10 5 10 8 10 9 5 10 9Pilbara 9 4 5 9 1 10 7 8 9 2 9 8Pine Creek 10 6 5 9 3 7 10 10 8 5 10 10Riverina 8 3 0 5 4 6 1 7 2 8 10 9Simpson Strzelecki Dunefields

10 9 3 4 2 6 7 1 6 10 10 9

Stony Plains 8 10 5 4 4 7 4 2 7 9 10 9Sturt Plateau 10 6 9 10 3 10 7 10 10 6 10 10Tanami 10 9 5 9 1 10 9 4 7 9 10 8Tiwi Cobourg 10 2 5 4 8 4 6 5 3 4 9 8Victoria Bonaparte 10 7 2 10 5 10 7 10 10 4 10 8Yalgoo 4 3 2 5 2 10 2 10 8 3 10 8

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Appendix 2, part 1. Spatially-averaged amounts of AussieGRASS-simulated pasture growth (kg ha-1) for rangeland bioregions. Pasture growth is accumulated from March of one year to February of the following.

IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Arnhem Coast 1811 1751 1633 1691 1674 1734 1656 1744 1679 1669 1870 1763Arnhem Plateau 2339 2244 2145 2188 2116 2222 2103 2220 2154 2081 2370 2255Brigalow Belt North 4375 1579 557 1488 868 1208 2578 5192 3105 3006 4904 3899Brigalow Belt South 2726 1324 532 1638 610 1461 863 3557 1072 2420 3192 2695Broken Hill Complex 549 367 85 353 229 486 153 290 224 364 1586 914Burt Plain 3082 1718 619 691 807 1055 1046 488 374 546 3843 967Cape York Peninsula 2058 1850 1598 1529 1875 1600 1856 1917 1894 1429 2538 1752Carnarvon 848 62 185 269 338 840 119 430 769 82 658 758Central Arnhem 2050 1858 1902 1873 1820 1885 1940 1989 1888 1899 2161 1926Central Kimberley 1754 1649 1417 1615 1466 1629 1544 1881 1629 1213 2255 1763Central Ranges 922 1622 221 657 601 832 355 511 338 391 1376 1245Channel Country 1136 357 149 215 116 214 221 149 236 722 2309 1082Cobar Peneplain 1666 1740 361 1545 1187 1856 791 1676 852 1908 2849 2943Coolgardie 709 365 81 540 233 336 233 99 247 232 122 336Daly Basin 2067 1973 1927 1957 1916 2018 1903 2071 1990 1840 2188 2054Dampierland 2002 1235 1362 1422 1300 1806 1625 1754 1669 1335 2270 1765Darling Riverine Plains 2726 1839 344 2113 1502 2368 801 2286 1359 2348 3563 3213Darwin Coastal 2013 2019 1981 1989 1993 2025 1924 2040 1982 1920 2064 2017Davenport Murchison Ranges

3086 1205 603 1112 267 926 1456 358 551 470 2876 1235

Desert Uplands 3549 1745 474 1087 817 1141 2804 4109 2920 2641 4265 2999Einasleigh Uplands 3669 2514 1110 1978 1794 2000 3364 3489 3427 1981 4452 2860Finke 1048 2324 251 357 341 281 79 114 234 205 2320 763Flinders Lofty Block 845 892 132 382 396 579 235 254 273 466 1735 1260Gascoyne 772 363 277 364 292 563 428 444 362 82 457 514Gawler 218 521 156 128 205 169 186 129 107 230 724 428Gibson Desert 648 891 324 417 370 580 430 498 316 131 431 791Great Sandy Desert 1335 1054 316 472 493 683 493 576 398 356 1369 1030

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IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Great Victoria Desert 437 751 222 254 366 300 212 177 165 123 576 758Gulf Coastal 2328 1964 2003 2020 1869 2019 2122 2096 1980 1921 2339 2257Gulf Fall and Uplands 2822 2018 1864 2183 1428 2022 2250 1956 1898 1860 3028 2564Gulf Plains 2946 1943 1337 1621 1490 1646 2553 2195 2180 1847 3175 2402Hampton 1258 1007 291 532 640 756 769 774 407 432 1364 1178Little Sandy Desert 743 606 435 463 363 616 631 561 339 132 534 842MacDonnell Ranges 2567 1902 444 468 668 565 369 331 391 540 3417 1058Mitchell Grass Downs 2916 1198 756 1000 515 837 1450 1199 1279 1688 2636 2065Mount Isa Inlier 3156 845 588 1058 708 999 1663 775 791 1124 2959 2117Mulga Lands 894 897 231 814 620 698 557 1304 477 1785 1380 1805Murchison 701 429 125 319 396 519 344 220 202 148 314 610Murray Darling Depression

1416 843 186 894 411 1509 460 638 380 933 2283 1762

Northern Kimberley 1795 1651 1841 1756 1863 1740 1871 1888 1789 1677 2089 1846Nullarbor 907 1040 198 210 423 608 483 380 140 146 1334 1355Ord Victoria Plain 2230 1856 1094 1741 1070 1934 1285 2193 1644 1257 2614 1803Pilbara 1194 530 435 495 398 962 625 628 747 268 627 852Pine Creek 1978 1942 1885 1939 1865 1950 1829 1997 1918 1822 2016 1940Riverina 2856 1997 560 2111 1483 2525 1118 1348 663 1926 3876 3022Simpson Strzelecki Dunefields

927 467 118 120 139 217 145 87 206 307 2561 534

Stony Plains 284 606 171 97 251 177 71 24 147 228 1059 438Sturt Plateau 2434 1950 1634 2003 1119 2241 1756 2065 1969 1717 2436 2082Tanami 2395 1361 629 980 370 1078 992 936 541 662 2651 1135Tiwi Cobourg 2637 2116 1792 2350 2401 2268 2103 2464 2306 2090 2773 2394Victoria Bonaparte 2321 2186 1794 2127 2049 2264 1999 2475 2128 1752 2680 2219Yalgoo 659 313 194 364 315 635 184 191 605 467 439 767

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Appendix 2, part 2. Deciles of AussieGRASS-simulated pasture growth for rangeland bioregions.

IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Arnhem Coast 9 8 1 3 2 6 1 7 3 2 10 8Arnhem Plateau 10 8 1 3 1 6 1 5 1 1 10 8Brigalow Belt North 9 2 0 2 1 1 5 10 6 6 9 8Brigalow Belt South 8 4 1 5 1 4 2 10 3 7 9 8Broken Hill Complex 7 5 1 5 3 7 2 4 3 5 10 10Burt Plain 10 10 7 7 8 9 8 6 4 6 10 8Cape York Peninsula 8 4 1 1 5 1 4 6 5 1 10 3Carnarvon 9 1 2 4 5 9 1 6 8 1 7 8Central Arnhem 9 2 4 3 1 3 5 7 3 4 10 5Central Kimberley 9 8 5 8 5 8 7 10 8 3 10 9Central Ranges 9 10 5 9 8 9 7 8 7 7 10 10Channel Country 10 7 2 4 1 4 4 2 4 9 10 9Cobar Peneplain 4 5 0 4 2 6 1 4 1 6 10 10Coolgardie 10 7 1 9 5 7 5 2 5 5 2 7Daly Basin 9 3 2 2 1 6 1 9 4 1 10 8Dampierland 10 3 4 5 3 9 7 8 8 4 10 8Darling Riverine Plains 7 4 0 5 3 6 1 5 2 6 10 9Darwin Coastal 6 6 3 3 4 7 1 8 3 0 9 6Davenport Murchison Ranges

10 9 8 9 5 9 10 6 8 7 10 9

Desert Uplands 8 4 1 2 1 2 7 10 7 6 10 7Einasleigh Uplands 9 5 1 3 2 4 8 8 8 3 10 6Finke 10 10 7 8 8 7 2 4 6 6 10 9Flinders Lofty Block 7 7 1 3 3 5 1 2 2 4 10 9Gascoyne 10 7 6 7 6 9 8 8 7 2 8 9Gawler 5 9 3 2 4 3 4 2 2 5 10 8Gibson Desert 10 10 9 9 9 10 9 10 9 5 10 10Great Sandy Desert 10 10 5 8 8 9 8 9 7 6 10 10

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IBRA 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12Great Victoria Desert 9 10 8 8 9 9 8 7 7 5 10 10Gulf Coastal 10 4 4 5 3 5 7 6 4 3 10 9Gulf Fall and Uplands 10 6 5 7 2 7 8 6 5 5 10 10Gulf Plains 10 6 1 4 2 4 9 7 7 5 10 8Hampton 10 10 3 6 7 8 8 8 4 5 10 10Little Sandy Desert 10 10 9 9 8 10 10 10 8 4 9 10MacDonnell Ranges 10 10 6 6 7 6 5 4 5 6 10 9Mitchell Grass Downs 10 7 4 6 2 4 8 7 7 9 10 9Mount Isa Inlier 10 6 4 7 5 6 8 5 5 7 10 9Mulga Lands 5 5 0 4 3 3 2 8 2 10 9 10Murchison 10 8 3 7 8 9 7 5 5 3 7 10Murray Darling Depression

8 4 1 4 1 8 2 3 1 5 10 10

Northern Kimberley 6 2 7 4 8 4 8 9 5 3 10 8Nullarbor 9 10 4 4 8 9 8 7 3 3 10 10Ord Victoria Plain 10 9 4 8 4 9 6 10 8 6 10 9Pilbara 10 6 5 6 4 10 7 8 9 2 8 9Pine Creek 9 7 2 6 1 7 1 10 4 1 10 6Riverina 8 4 0 4 2 6 1 2 1 3 10 9Simpson Strzelecki Dunefields

10 9 3 3 4 6 4 1 6 7 10 9

Stony Plains 8 10 6 4 8 6 2 0 5 7 10 9Sturt Plateau 10 8 5 8 2 10 6 9 8 6 10 9Tanami 10 9 6 8 3 9 9 8 5 7 10 9Tiwi Cobourg 9 2 1 4 5 3 2 7 4 1 10 5Victoria Bonaparte 10 7 1 6 5 9 4 10 6 1 10 8Yalgoo 7 2 1 3 2 6 1 1 6 4 3 8

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