<html><head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; color: rgb(0, 0, 0); font-size: 14px; font-family: Calibri, sans-serif;"><div>Hi Matt,</div><div><br></div><div>From a recent presentation from the Australian Intergovernmental Committee on Surveying and Mapping [1]:</div><div><br></div><div><br></div><div>“Absolute difference between GDA94 and ITRF will exceed 1.8 metres by 2020”</div><div><br></div><div><br></div><div>This presentation was referring to a proposed dynamic datum: GDA2020 (which will raise a wide range of challenging data management issues).</div><div><br></div><div>I suggest following up with ICSM for an authoritative answer.</div><div><br></div><div>Bruce</div><div><br></div><div>[1] <a href="http://www.icsm.gov.au/publications/PCG-SSSC_2013_Canberra.pdf">http://www.icsm.gov.au/publications/PCG-SSSC_2013_Canberra.pdf</a> </div><div><br></div><div><br></div><div><br></div><span id="OLK_SRC_BODY_SECTION"><div style="font-family:Calibri; font-size:11pt; text-align:left; color:black; BORDER-BOTTOM: medium none; BORDER-LEFT: medium none; PADDING-BOTTOM: 0in; PADDING-LEFT: 0in; PADDING-RIGHT: 0in; BORDER-TOP: #b5c4df 1pt solid; BORDER-RIGHT: medium none; PADDING-TOP: 3pt"><span style="font-weight:bold">From: </span>Matt Boyd <<a href="mailto:mattslists@gmail.com">mattslists@gmail.com</a>><br><span style="font-weight:bold">Date: </span>Tuesday, 30 September 2014 14:17<br><span style="font-weight:bold">To: </span>qgis-user <<a href="mailto:qgis-user@lists.osgeo.org">qgis-user@lists.osgeo.org</a>><br><span style="font-weight:bold">Subject: </span>[Qgis-user] OT: IRTF to GDA94 difference<br></div><div><br></div><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="BORDER-LEFT: #b5c4df 5 solid; PADDING:0 0 0 5; MARGIN:0 0 0 5;"><div dir="ltr">Hi fellow QGIS people,
<div>I'd like an easy (as in if it's too hard I probably won't have time to do it) way to confirm the drift on GDA94 compared to UTM. I've done a little digging and haven't been able to find anything except "Australia is moving approximately NE at a rate of
7cm per year and in 2005 it was 77cm". Having said that, I'm a little hazy on if UTM is the worldwide reference and how it's related to IRTF.</div><div><br></div><div>Is there anywhere online that works this out automatically?</div><div><br></div><div>Thanks</div><div>Matt</div></div></blockquote></span></body></html>