A model built from mapped sources, not an observation or a survey map. Bigger squares mean less data, never worse nature.One 320 m square of Hobsons Bay, around Railway Place in Williamstown.
Railway Place, Williamstown: a model from mapped sources
Department of Energy, Environment and Climate Action (Victoria), Parks and Conservation Reserves (PARKRES) · GDA2020 (as served by the Victorian Open Data Platform)
repair: 28 invalid geometries made valid (shapely make_valid); 18 stray lower-dimension parts left by repairs removed
merge: parts sharing prims_id merged into one feature (5401 parts merged away); hectares summed from the source's per-part values
tile: tippecanoe to PMTiles, zoom 0-18, layer "parkres"
list: parkres.features.json: every feature's attributes and bounding box, for the list view
outlines: parkres.outlines/<xx>.json: each outline, by the first two hex digits of the SHA-1 of its id
index: parkres.index.json: each feature's id, name, type, state and bounding box, for suggesting place outlines
Cite as: Department of Energy, Environment and Climate Action (Victoria), Parks and Conservation Reserves (PARKRES), CC-BY-4.0; shown in PLOT from a display file (sha256 0eabc6abaac6).
Department of Transport and Planning (Victoria), Vicmap Admin - Local Government Area (LGA) Polygon Aligned to Property · GDA2020 (as served by the Victorian Open Data Platform) · aligned to property boundaries
repair: 5 invalid geometries made valid (shapely make_valid); 4 stray lower-dimension parts left by repairs removed
tile: tippecanoe to PMTiles, zoom 0-18, layer "lga"
list: lga.features.json: every feature's attributes and bounding box, for the list view
outlines: lga.outlines/<xx>.json: each outline, by the first two hex digits of the SHA-1 of its id
index: lga.index.json: each feature's id, name, type, state and bounding box, for suggesting place outlines
Cite as: Department of Transport and Planning (Victoria), Vicmap Admin - Local Government Area (LGA) Polygon Aligned to Property, CC-BY-4.0; shown in PLOT from a display file (sha256 92025b601a6b).
Every feature, as a list · 1 (large layers: those in view)
Up and down arrows move through the list; the map follows.
Parks and conservation reservesthe 0 in view
Name
Type
Managed by
Area (ha)
IUCN category
Council areas
Council
Official name
ABS code
HOBSONS BAY
HOBSONS BAY CITY
23110
See
What's here
Each card is one kind of habitat. Under it, each official type's own area here, from its own map or model and year, so you can see then and now. Areas are never added together. A dashed name is PLOT's proposal for where a type belongs.
Where they are, confirmed by a person. Being here is not an effect on the place.
Not looked at yet: pressures, protection, rules and obligations, who's involved. That is not the same as nothing being there.
Traditional Owner knowledge:none is shown for this place yet. It appears only from Traditional Owner organisations' own published statements, or with their consent. A Traditional Owner organisation can add its statement or ask for a correction.
See
Weather and climate
The weather Hobsons Bay has had, the climate it had in the , and what it would have under +1.5, +2 and +3 °C of . Values are for the its outline covers.
Mend
Next steps
Next step · proposed
Overlay the Ramsar and KBA boundaries with the Hobsons Bay boundary
Barrier. It is unknown how much of the Ramsar site and the KBA lies inside Hobsons Bay.
Proposed action. Load the official boundaries and compute the overlaps by code, recording them as co-located links with areas.
Done when. Co-located links with overlap areas are on the record, each citing the boundary datasets.
Drafted by AI (claude-opus-5-5) · Reviewed by a person at PLOT
Ask the land manager.A ready-made question you can send (coming)
Come to a walk.Local walks and working days (coming)
Plot
How we know
15 claims from 7 sources, from 4 publishers. Every claim links to the page and passage it comes from.
PLOT hasn't yet worked through the 16 questions its sourcing protocol asks about a place. 5 of the claims here were found before the protocol existed. The questions
Place summary (compiled from the published claims listed)
Who said it
Compiled by PLOT from the published claims listed
Period
Claims cover 1850–2027 (5 of 15 undated)
Checked
Reviewed (step 3 of 4)
Open questions
None open
What PLOT looked for and didn't find
No condition measures found for council conservation areas
Council material gives areas and actions but no vegetation quality, habitat hectare or similar condition scores.
What would close it: Any condition assessment of council reserves, with method and date
No total counts of plant, animal or threatened species for Hobsons Bay
The council strategy lists examples of threatened species but gives no totals.
What would close it: A species list for the municipality with its source and date, for example from the Victorian Biodiversity Atlas, counted by code
One 320 m square of Hobsons Bay, around Railway Place in Williamstown. A model built from OpenStreetMap extract, Vicmap trees, hydro, parks and native vegetation models, ESA WorldCover 10 m 2021, Copernicus Sentinel-2, Overture Maps buildings; colour is land cover, never condition.
14.8 °C overnight minimum · SILO grid, the latest day it covers. Not a live reading.
Rain, September 2026
17 mm
Reference for the month: 52 mm
The last twelve months
Annual rainfall
523 mm
reference 591 mm · −11% · Oct 2025 to Sept 2026
Days at or above 35 °C
8
reference 9 a year · Oct 2025 to Sept 2026
Mean maximum temperature, warmest month
28.0 °C
+1.1 °C vs reference · Oct 2025 to Sept 2026
Annual rainfall since 1889, against the reference band
Observed grid, one point a year; band = 1961–1990, 10th to 90th percentile; latest full year 2025: 502 mm.
Mean annual temperature since 1910
Observed grid, one point a year; band = 1961–1990, 10th to 90th percentile; latest full year 2025: 15.9 °C.
This place under warming levelsShowHide
Modelled: the median change across climate models at each level, applied to this place's 1961–1990. Hover a value for the range across models.
Measure
Reference 1961–1990
Now
+1.5 °C
+2 °C
+3 °C
Mean annual temperature
14.8 °C
15.4 °C
15.9 °C
16.4 °C
17.4 °C
Annual rainfall
591 mm
501 mm
569 mm
576 mm
554 mm
Days at or above 35 °C
9
11
12
14
18
Mean sea level, trend
—
2.6 mm a year (Stony Point tide gauge, since 1993)
not computed
not computed
not computed
Sea levelShowHide
2.6 mm a year
1993–2025: 2.6 mm a year (95%: 1.5 to 3.6)
1.7 mm a year
1894–2024: 1.7 mm a year (95%: 1.4 to 1.9); 1993–2024: 1.4 mm a year (95%: 0.3 to 2.5). PSMSL lists this record as not research quality: it lacks a continuous datum, so changes across its gaps may be datum shifts, not sea level.
This place is outside its envelope on mean annual temperature and days at or above 35 °c.
Share of its Hobsons Bay extent outside now: 82%
How this is calculatedShowHide
Review status: Unreviewed computed draft · method v0.1. Only a person marks a method reviewed.
Gridded weather and climate for an extent climate.series.grid_extract v0.1 · draft
SILO 0.05° daily and monthly grids (Queensland Government, CC BY 4.0) read for the cells a subject's mapped extent touches, each cell weighted by the share of the extent inside it (areas in Australian Albers). A year needs 90% of its days (every month, for rainfall); otherwise it is flagged, never zero or filled. Last twelve months: the twelve complete months before the latest SILO update. Grid cells miss microclimate and refugia; SILO is interpolated from stations, so a cell is not a measurement.
Mean sea level and its trend climate.sealevel.trend v0.1 · draft
PSMSL monthly means. Annual means need 11 of 12 months. Trend: least squares on deseasonalised monthly means, with a 95% interval widened for month-to-month persistence. Williamstown is in PSMSL's metric set only (no continuous datum), so its trend may include datum shifts and carries that warning; Stony Point is the nearest research-quality gauge.
Known limits
Grid cells (about 5 km) miss microclimate and refugia.
Warming levels use one change per month for all of southern Australia (IPCC Atlas region SAU), not downscaled.
Unknown whether any Ramsar-listed land lies inside the City of Hobsons Bay
The boundary description includes parts of the Cheetham Wetlands but names no local government areas. The KBA factsheet places part of the Cheetham Wetlands between Altona and Altona Meadows.
What would close it: An overlay of the Ramsar boundary with the Hobsons Bay LGA boundary, computed by code
See coverage: how far PLOT has looked, question by question
Coverage: how well PLOT has looked
Coverage describes how well PLOT has looked for evidence, question by question and channel by channel. It is not a score of nature's condition.
Counts the claims PLOT's sourcing for Hobsons Bay found, including claims about places within it (such as reserves), so they can differ from the claims listed on the place itself.