SEVERE WEATHER EVENTS DATABASE DEVELOPMENT
METHODOLOGY
Green Cross Australia (GCA) has worked with a team of staff,
research experts, university interns and volunteers to develop a
severe weather events database that includes over 3,000 floods,
cyclones, severe thunderstorms, bushfires and storm surge events
going back to 1850. Each of these events is listed across 3,275
suburbs that may have been impacted, based on the methodology
described below.
If you know of an event that is not included in our events
database, we would appreciate your help in developing our database
by contacting us
and sharing the details. We will need to know what areas were
affected, dates and a description of the event.
Core data used in the Harden Up severe weather events database
is sourced from a number of Bureau of Meteorology (BOM) databases
and from the Attorney-General's Department Disasters Database which is managed
by the Australian Emergency Management Institute.
WHY THE HARDEN UP DATABASE LISTS BY SUBURB AND NOT POST
CODES
Queensland has over 3,000 suburbs, and some postcodes cover more
than 30 suburbs (a list of Queensland postcodes is here). The geographic size of some postcodes is
very large compared to suburb boundaries. Because Harden Up offers
a historical picture of local severe weather history, GCA has used
suburbs rather than postcodes to list events so that we can drill
down to a more meaningful local weather history for each
location.
Harden Up lists events by suburb for community awareness and
educational purposes using the Australia Post postcode/suburb list
for Queensland which can be found here.
FLOOD EVENT LISTINGS
The primary source of flood data listed in the Harden Up
database is the Bureau of Meteorology (BoM) "Queensland Flood
History" which is found here. The following methodology was used to
identify why suburbs may have been impacted by each of the major
floods listed by BoM.
Step 1: Identify which catchment(s) each flood drained into
where clear historical information is available.
The Harden Up database records in
which river catchment(s) a flooding event occurred in. A document
surmising a history of major flood events in Queensland can be
viewed here. This document lists flood events in
Queensland from 1857 to 2010.
Queensland has forty three coastal
and inland river catchments.
In order to identify which
Queensland suburbs may have been impacted by each of these major
historical floods, GCA staff and university interns reviewed the
full text description for each event in the BoM archives to
identify all regions, towns and/or suburb names mentioned. In this
way we were able to identify all river catchments impacted by each
flood.
Step 2: Identify which catchment(s) each flood drained into
where unclear historical information is available.
In some cases BoM archives identify
an approximate date and general area impacted, without naming
specific locations. For these events, GCA identified each possible
river impacted based on general locational descriptions (in some
cases for older events, descriptions are as broad as "Southeast
Queensland" or "Central Queensland", so all river catchments in the
region may have been impacted).
To ascertain whether a river was
impacted, GCA referred to historical BoM River Gauge Data for that
river to see whether a major river gauge measure was triggered
around the approximate date mentioned.
For example, the river gauge history
for the Fitzroy River is here.
The previous flooding history for
the Fitzroy River found on the above link indicates a major peak
was recorded around 1919, when the river peaked above the 10 metre
gauge height:
By reviewing similar river gauge
data for all possible rivers impacted by each event, GCA was able
to identify impacted river catchments for each of the major floods
listed in the BOM major flood archives.
Step 3: Identify which suburbs may have been impacted by
each flood.
GCA linked events to suburbs
according to which suburbs are located within each river catchment
area.
The Queensland Government Department
of Environment and Resource Management (DERM) manages Queensland
river catchment map boundaries, which are used by the research
community including BoM. DERM river catchment areas can be found here. The number of suburbs listed within each
catchment map varies widely from a handful in some cases, to over a
dozen suburbs in other cases, depending on the distribution of
population around each Queensland river.
Some local government authorities
have developed and made available flood maps that enable the public
to locate historical flooding patterns around rivers. Around 200
suburb level flood maps developed by Brisbane City Council are
available in www.hardenup.org - for example, the
flood map for Milton is pictured below.

By using these types of maps where
available, Queenslanders can build an understanding of the
historical flood risks in their neighbourhood locations, and can
better understand whether historical floods around their local
river may have impacted on their homes or immediate neighborhood
areas. However, flood maps are not available for all areas across
Queensland, and new methodologies for flood maps are being
developed through various inquiries including the Flood Insurance
Inquiry.
Therefore in order to identify which
suburbs may have been impacted in each historical flood listed in
the Harden Up database, GCA has included all suburbs within each
river catchment impacted for each event linked to that river
catchment. This means that if your suburb is located within an
affected drainage basin area, your suburb will be listed for that
particular event, even if the flood waters may not have reached
your home or immediate neighborhood.

EAST COAST LOW EVENT LISTINGS
Find out more about East Coast Lows here.
Some of the more intense low pressure systems outside the
tropics are capable of matching the power and destructive potential
of many tropical cyclones. In a league of their own in this regard
are the class of cyclones known as "East Coast Lows", which as
their name implies, develop near the east coast between southern
Queensland and Tasmania. For purposes of listing these events in
the Harden Up database, they are classified as "severe
thunderstorms".
BoM experts and insurers are focusing intensively on these kinds
of events because of their potentially significant property and
safety impacts. During 2012, BoM will release a new East Coast Low
database and this will be incorporated into the Harden Up database
in future.
The primary source of East Coast Low data listed in the Harden
Up database currently is a database archive created by Jeff
Callaghan - a retired senior BoM forecaster who is Chair of the
Harden Up Steering Committee. You can download this archive here. Video interviews with Jeff Callaghan are
found throughout the Harden Up Be Aware section.
The affected area for each East Coast Low event was determined
by referring to the corresponding BoM daily rainfall records, which
are found here. GCA identified geographical areas that
received significant rainfall on the day(s) listed in each archive
event using these BoM rainfall records.
Over the next twelve months, in addition to incorporating the
upcoming BoM East Coast Low archive into the Harden Up database,
GCA will work to refine geographic impact areas using more refined
geo-spatially located daily rainfall plot data.
SEVERE STORM EVENT LISTINGS
Find out more about severe storms here.
The primary source of severe storm information in the Harden Up
database is an archive created by Jeff Callaghan, a retired senior
BOM forecaster who is Chairman of the Harden Up Steering Committee.
You can download this archive here.
GCA determined which areas were impacted during each event by
reviewing the historical archive text descriptions. In cases where
only one location was mentioned, the event was attributed to all
suburbs within a 10km radius of that location on Google Earth.

In some cases, more than one location is identified in the event
archive description. In these cases, the event was recorded as a
series of event locations each with their own 10km radius.
STORM SURGE EVENT LISTINGS
Storm surge events often accompany cyclones. The source
information for storm surge events was the cyclone database (more
detail on that below). The events where a storm surge was described
in the report were extracted from the cyclone event list to form
the storm surge database. This database currently contains 80
recorded storm surge events.
These events where located at the point of the major storm surge
listed, and a 10 kilometres radius was drawn around this point to
identify the relevant suburbs.
For more information on some particular storm surges, see the
two archive documents in the resources section and the bottom of
this page, which provide details of storm surges which occurred in
the Gulf of Carpentaria.
BUSHFIRE EVENT LISTINGS
The Harden Up Queensland bushfire database needs further
development.
GCA has sourced major historical bushfires from the following
references:
GCA carefully reviewed the available text descriptions for each
event listed in each of these three references areas. In cases
where a burnt area was specified, an area of that size (around the
latitude and longitude mark identified as the main location) was
specified.
Bushfires with no specified burnt area were assumed to have an
impact radius of 5km around the main location.
For bushfires larger than this - over a number of towns - an
impact area was drawn around the towns listed, and the a fire is
listed for all suburbs within this area in the Harden Up
database.
CGA and our research partners are keenly interested in
developing our historical understanding of major historical
Queensland bushfires. GCA is engaging with the Rural Fire
Association of Queensland and other stakeholders to further develop
the Harden Up Bushfire database.
If you have historical bushfire information please let us know
by contacting GCA at info@greencrossaustralia.org
CYCLONE EVENT LISTINGS
The main source of information about cyclone tracks in the
Harden Up database is the "BoM Tropical Cyclone Track Database".
You can find out more about historical BoM cyclone information here.
Two cyclone archives included in the Harden Up database can be
downloaded at the bottom of this page.
The Bureau of Meteorology provided GCA with a database covering
all recorded tropical cyclone tracks over the region south of the
equator between 90E and 160E. For the Harden Up project, all
cyclone tracks that cross the QLD State boundary were selected. The
corridor width for each of these cyclone paths was conservatively
chosen to be the maximum width of recorded gale force winds (this
is the mean radius from the system centre of the extent of winds,
gale force 17m/s or above).
Before 1985, recorded gale force winds are not specified in the
BoM Tropical Cyclone Track Database. GCA selected a nominal radius
of 200km (the approximate average of recorded data) around the
cyclone track. These cyclone track corridors were then overlayed
against the QLD suburb locations in order to determine which
suburbs may have been affected by a specific cyclone.

In a number of cases, a written description of cyclone effects
is recorded, but the cyclones did not reach Queensland but rather
veered offshore. In some of these cases, a map indicating the
coastal affected area was available from BoM and suburbs within
this map are listed in the Harden Up database. Where this was not
the case, GCA estimated which coastal area was most impacted by an
offshore event recorded, and a standard radius of 25km around the
described location was applied for purposes of listing the suburbs
in the Harden Up database.

For all cyclone events a centre point, or main impact location
is specified as one latitude/longitude mark. When you click on the
'more' link, this is the location that will display on the map
alongside the event details. For example the central impact
location for Cyclone Yasi is near Mission beach as shown in the
"Region Map" at the left of the Cyclone Yasi case study page:

This section provides metadata information ("data about data")
for the datasets referred to above.
DERM Catchment Maps (or Drainage Basins)
Date downloaded: September 2011
Description: The boundaries and names of the Queensland Drainage
Basins are as defined by the Australian Water Resources Management
Committee (WRMC). Information includes the name and number of each
drainage basin. The capture scale for this dataset is 1:100 000.
This data was downloaded in September 2011. The data is publicly
available here: http://www.nrm.qld.gov.au/services_resources/item_list.php?category_id=10&topic_id=28
BoM Flood History
Date range: 1941 - present
http://www.bom.gov.au/qld/flood/fld_history/index.shtml
BoM River Gauge Data
Date range: 1890 - present
http://www.bom.gov.au/qld/flood/fld_history/index.shtml
BoM Detailed Reports on Notable Queensland Floods
Date range: 1958 - present
http://www.bom.gov.au/qld/flood/fld_reports/reports.shtml
ARCHIVE: Known Impacts of Tropical Cyclones, East Coast,
1858-2008
ARCHIVE: Known Impacts of Tropical Cyclones, Gulf of
Carpentaria, 1885-2007
QLD suburb locations
Queensland suburbs were identified using the Australia Post
listing of postcodes and suburbs located here:
http://auspost.com.au/products-and-services/download-postcode-data.html