As part of the ongoing investigation into our evolving climate, we routinely process and analyse meteorological data from successive years, conducting comparative assessments to reveal emerging trends and patterns.

Our previous temporal analyses only focused on examining variations in various weather elements with the results of EnergyPlus simulations of the three archetypes used in our Weather and Energy Index (EWEI), specifically targeting HVAC systems and heating and cooling dynamics within buildings. We have added the results of System Advisor Model (SAM) photovoltaic (PV) system simulations to enhance the comprehensiveness of our investigation up to 2023. The analysis for other capital cities can be viewed here.

Now, we are extending our previous temporal analysis to 2024 for all eight capital cities, so readers will soon be able to access our recent analysis on our blog.

For the analysis of weather elements, we examined the temporal variations in dry bulb temperature, humidity, wind speed, global horizontal irradiation (GHI), direct normal irradiation (DNI), and average precipitation. The analysis involved averaging these elements over three 15-year periods—1990-2004, 2005-2019, and the latest 15-year period from 2010 to 2024—and then comparing the results. A comparison between data from the latest 15 years, the data corresponding to the years and months specified in Industry Standard Meteorological Year (ISMY) files, and the data exclusively from 2024 was also undertaken. ISMYs were originally developed for application in house energy rating software used in NatHERS and derive from historical Bureau of Meteorology (BOM) weather data spanning from 1990 to 2015. Over time, they have become the industry’s de facto standard. It is therefore important to compare against ISMY data, as it provides a reference to gauge alignment with established benchmarks and understand the significance of temporal variations in weather elements.

First of all, we compared 2024 weather data with 2023 data. Overall, summer months (December-February) had higher temperatures (0.74°C), more humidity (0.61g/kg) and lower GHI and DNI (24.93Wh/m² and 48.66Wh/m²), while winter months (June-August) had lower temperatures (0.14°C), lower humidity (0.10g/kg) and less GHI and DNI (13.72 Wh/m² and 42.07Wh/m²). Also, overall, 2024 shows a different precipitation pattern compared with 2023 in most months but from May to July had big differences (157.40mm in May, 350.60mm in June and 50.60mm in July).

Comparing 1990-2004 with 2010-2024 showed an increase in Sydney’s mean temperature of 0.43°C (2.40%), an increase in moisture of 4.72%, and a big increase in wind speed of 10.13%. GHI and DNI had decreases of 2.86% and 10.07% respectively. Meanwhile, comparing 2005-2019 with 2010-2024 showed a decrease in the mean temperature of 0.05°C (0.30%), an increase in moisture of 2.05%, an increase in wind speed of 1.85%, and a decrease in GHI and DNI of 1.48% and 3.67% respectively. The small decrease in mean temperature and increase in GHI for 2005-2019 vs 2010-2024 is likely a result of 2005-2019 experiencing comparatively higher annual average dry bulb temperatures and GHI when compared to other years.

Average precipitation in 2010-2024 was 8.44% higher than in 1990-2004, and 14.96% higher than in the 2005-2019 period. When comparing monthly averages, overall, precipitation in 2010-2024 was higher than in 2005-2019. These big differences between 1990-2004 and 2010-2024 will affect building simulation model results for heating and cooling.

Compared to the ISMY period (1990–2015), the most recent 15 years (2010–2024) show notable climate changes: mean temperature increased by 0.22°C (1.24%), moisture rose by 3.66%, and wind speed grew by 3.03%. Additionally, GHI and DNI decreased by 0.66% and 2.47% respectively. Noticeably, average precipitation rose by 34.9% (28.07mm). These shifts highlight distinct climatic trends between the two periods.

The annual trends of energy consumption reveal intriguing patterns across various building archetypes. All archetypes had increasing trends for cooling energy consumption from 1990-2024, 1990-2004, 2005-2019, 2010-2024 as well as in the 26-year period of 1990-2015 still in widespread use for building simulations despite the significantly warmer subsequent decade. In contrast, heating energy consumption followed an opposite pattern with decreasing trends for all archetypes in the 1990-2024, 2005-2019 and 2010-2024 periods, but increasing trends in the 1990-2004 and 1990-2015 periods for 3-storey and 10-storey offices. These trends are indicative of a changed climate and highlight the importance of using relevant climate files from the more recent 2010-2024 period in building energy simulations rather than the older ISMY data.

As part of the ongoing investigation into our evolving climate, we routinely process and analyse meteorological data from successive years, conducting comparative assessments to reveal emerging trends and patterns.

Our previous temporal analyses only focused on examining variations in various weather elements with the results of EnergyPlus simulations of the three archetypes used in our Weather and Energy Index (EWEI), specifically targeting HVAC systems and heating and cooling dynamics within buildings. We have added the results of System Advisor Model (SAM) photovoltaic (PV) system simulations to enhance the comprehensiveness of our investigation up to 2023. The analysis for other capital cities can be viewed here.

Now, we are extending our previous temporal analysis to 2024 for all eight capital cities, so readers will soon be able to access our recent analysis on our blog.

For the analysis of weather elements, we examined the temporal variations in dry bulb temperature, humidity, wind speed, global horizontal irradiation (GHI), direct normal irradiation (DNI), and average precipitation. The analysis involved averaging these elements over three 15-year periods—1990-2004, 2005-2019, and the latest 15-year period from 2010 to 2024—and then comparing the results. A comparison between data from the latest 15 years, the data corresponding to the years and months specified in Industry Standard Meteorological Year (ISMY) files, and the data exclusively from 2024 was also undertaken. ISMYs were originally developed for application in house energy rating software used in NatHERS and derive from historical Bureau of Meteorology (BOM) weather data spanning from 1990 to 2015. Over time, they have become the industry’s de facto standard. It is therefore important to compare against ISMY data, as it provides a reference to gauge alignment with established benchmarks and understand the significance of temporal variations in weather elements.

First of all, we compared 2024 weather data with 2023 data. Overall, summer months (December-February) had higher temperatures (0.92°C), more humidity (0.35g/kg) and less GHI and DNI (8.15 Wh/m² and 18.38Wh/m²), while winter months (June-August) had much higher temperatures (2.14°C), high humidity (0.72g/kg), and less GHI and DNI (12.69 Wh/m² and 37.11Wh/m²). Also, overall, 2024 shows near 0 precipitation from January to April and much higher precipitation in August and October (96.6mm and 43mm higher). However, total precipitation is similar to 2023.

Comparing 1990-2004 with 2010-2024 showed an increase in Perth’s mean temperature of 0.60°C (3.33%), a slight decrease in moisture of 0.34%, and a significant increase in wind speed of 16.38%. GHI and DNI had high increases of 2.86% and 1.18% respectively. Meanwhile, comparing 2005-2019 with 2010-2024 showed a decrease in the mean temperature of 0.31°C (1.66%), a decrease in moisture of 0.42%, an increase in wind speed of 1.03%, and an increase in GHI and DNI of 1.11% and 0.53% respectively. Compared to the periods 1990–2004 and 2005–2019, the increase in mean temperature, GHI, and DNI, along with lower precipitation and similar humidity in 2010–2024, contributed to a warmer Perth.

Average precipitation in 2010-2024 was 11.19% lower than in 1990-2004, and 1.63% lower than the 2005-2019 period. When comparing monthly averages, overall the 2010-2024 period had similar precipitation to 1990-2004 and 2005-2019 except for May to July in 1990-2004.

Compared to the ISMY period (1990–2015), the most recent 15 years (2010–2024) show notable climate changes: mean temperature increased by 0.32°C (1.74%), moisture decreased by 0.78%, and wind speed grew by 4.52%. Additionally, GHI and DNI increased by 2.75% and 3.58% respectively. Average precipitation also decreased by 9.58%. These shifts highlight distinct climatic trends between the two periods.

The annual trends of energy consumption reveal intriguing patterns across various building archetypes. All archetypes had increasing trends for cooling energy consumption from 1990-2024, as well as in the 15-year periods of 1990-2004, 2005-2019 and 2010-2024, while heating energy consumption had decreasing trends for the supermarket in all periods. For the 3-storey and 10-storey offices, heating energy consumption increased from 1990-2004 and 1990-2015 but decreased from 2005-2019 and 2010-2024. These trends are indicative of a changed climate and highlight the importance of using relevant climate files from the more recent 2010-2024 period in building energy simulations rather than the older ISMY data.

As part of the ongoing investigation into our evolving climate, we routinely process and analyse meteorological data from successive years, conducting comparative assessments to reveal emerging trends and patterns.

Our previous temporal analyses only focused on examining variations in various weather elements with the results of EnergyPlus simulations of the three archetypes used in our Weather and Energy Index (EWEI), specifically targeting HVAC systems and heating and cooling dynamics within buildings. We have added the results of System Advisor Model (SAM) photovoltaic (PV) system simulations to enhance the comprehensiveness of our investigation up to 2023. The analysis for other capital cities can be viewed here.

Now, we are extending our previous temporal analysis to 2024 for all eight capital cities, so readers will soon be able to access our recent analysis on our blog.

For the analysis of weather elements, we examined the temporal variations in dry bulb temperature, humidity, wind speed, global horizontal irradiation (GHI), direct normal irradiation (DNI), and average precipitation. The analysis involved averaging these elements over three 15-year periods—1990-2004, 2005-2019, and the latest 15-year period from 2010 to 2024—and then comparing the results. A comparison between data from the latest 15 years, the data corresponding to the years and months specified in Industry Standard Meteorological Year (ISMY) files, and the data exclusively from 2024 was also undertaken. ISMYs were originally developed for application in house energy rating software used in NatHERS and derive from historical Bureau of Meteorology (BOM) weather data spanning from 1990 to 2015. Over time, they have become the industry’s de facto standard. It is therefore important to compare against ISMY data, as it provides a reference to gauge alignment with established benchmarks and understand the significance of temporal variations in weather elements.

First of all, we compared 2024 weather data with 2023 data. Overall, summer months (December-February) had higher temperatures (0.1°C) and humidity (0.19g/kg) while less GHI and DNI (8.52 Wh/m² and 12.94Wh/m²). Winter months (June-August) had lower temperatures (0.44°C), lower humidity (0.25g/kg) and higher GHI and DNI (1.61 Wh/m² and 7.43Wh/m²). In addition, 2024 had nearly 45.7% higher precipitation than 2023. Especially, January, March and November 2024 had higher precipitation than 2023 (253.4mm in January, 240.8mm in March and 147.4mm in November).

Comparing 1990-2004 with 2010-2024 showed an increase in Darwin’s mean temperature of 0.34°C (1.26%), an increase in moisture of 1.5%, and a significant increase in wind speed of 13.71%. GHI and DNI had decreases of 3.88% and 11.52% respectively. Meanwhile, comparing 2005-2019 with 2010-2024 showed an increase in the mean temperature of 0.21°C (0.78%), an increase in moisture of 1.67%, a decrease in wind speed of 5.13%, and a decrease in GHI and DNI of 2.65% and 5.52% respectively.

Average precipitation in 2010-2024 was 1.90% lower than in 1990-2004, and 0.64% higher than the 2005-2019 period. When comparing monthly averages, precipitation 2010-2024 for every month was generally similar to 2005-2019 and 1990-2004.

Compared to the ISMY period (1990–2015), the most recent 15 years (2010–2024) show notable climate changes: mean temperature increased by 0.23°C (0.84%), moisture rose by 2.02%, and wind speed decreased by 0.77%. Additionally, GHI and DNI decreased by 4.02% and 10.47% respectively. In addition, average precipitation decreased by 1.35% (2.06mm). These shifts highlight distinct climatic trends between the two periods.

The annual trends of energy consumption reveal intriguing patterns across various building archetypes. All archetypes had increasing trends for cooling energy consumption from 1990-2024, 2005-2019 and 2010-2024 while decreasing in 1990-2004 and 1990-2015. These trends are indicative of a changed climate and highlight the importance of using relevant climate files from the more recent 2010-2024 period in building energy simulations rather than the older ISMY data.

As part of the ongoing investigation into our evolving climate, we routinely process and analyse meteorological data from successive years, conducting comparative assessments to reveal emerging trends and patterns.

Our previous temporal analyses only focused on examining variations in various weather elements with the results of EnergyPlus simulations of the three archetypes used in our Weather and Energy Index (EWEI), specifically targeting HVAC systems and heating and cooling dynamics within buildings. We have added the results of System Advisor Model (SAM) photovoltaic (PV) system simulations to enhance the comprehensiveness of our investigation up to 2023. The analysis for other capital cities can be viewed here.

Now, we are extending our previous temporal analysis to 2024 for all eight capital cities, so readers will soon be able to access our recent analysis on our blog.

For the analysis of weather elements, we examined the temporal variations in dry bulb temperature, humidity, wind speed, global horizontal irradiation (GHI), direct normal irradiation (DNI), and average precipitation. The analysis involved averaging these elements over three 15-year periods—1990-2004, 2005-2019, and the latest 15-year period from 2010 to 2024—and then comparing the results. A comparison between data from the latest 15 years, the data corresponding to the years and months specified in Industry Standard Meteorological Year (ISMY) files, and the data exclusively from 2024 was also undertaken. ISMYs were originally developed for application in house energy rating software used in NatHERS and derive from historical Bureau of Meteorology (BOM) weather data spanning from 1990 to 2015. Over time, they have become the industry’s de facto standard. It is therefore important to compare against ISMY data, as it provides a reference to gauge alignment with established benchmarks and understand the significance of temporal variations in weather elements.

First of all, we compared 2024 weather data with 2023 data. Overall, summer months (December-February) had higher temperatures (1.09°C) and humidity (0.84g/kg) while slightly less GHI and DNI (3.33 Wh/m² and 0.24Wh/m²). Winter months (June-August) had lower temperatures (0.26°C), humidity (0.09g/kg), and GHI and DNI (2.12 Wh/m² and 15.04Wh/m²). In addition, average precipitation in 2024 was 20.2% (12mm) lower than 2023, resulting from significantly lower precipitation in March and November 2024 compared to 2023.

Comparing 1990-2004 with 2010-2024 showed an increase in Canberra’s mean temperature of 0.34°C (2.60%), a big increase in moisture of 5.32%, and an increase in wind speed of 22.52%. GHI and DNI had an increase of 0.84% and a decrease of 2.45%, respectively. Meanwhile, comparing 2005-2019 with 2010-2024 showed a decrease in the mean temperature of 0.21°C (1.51%), an increase in moisture of 2.89%, a decrease in wind speed of 0.87%, and a decrease in GHI and DNI of 0.90% and 3.43% respectively. The small decrease in mean temperature and GHI for 2005-2019 vs 2010-2024 is likely a result of 2005-2019 experiencing comparatively higher annual average dry bulb temperatures and GHI when compared to other years.

Average precipitation in 2010-2024 averaged 9.8% higher than in 1990-2004, and 16.33% higher than the 2005-2019 period. When comparing monthly averages, precipitation from 2010 to 2024 for every month was generally higher than other periods except from late autumn to winter (May to August). These big differences among 1990-2004, 2005-2019 and 2010-2024 periods will affect building simulation model results for heating and cooling.

Compared to the ISMY period (1990–2015), the most recent 15 years (2010–2024) show notable climate changes: mean temperature increased by 0.05°C (0.39%), moisture rose by 3.96%, and wind speed rose by 8.2%. Additionally, GHI and DNI decreased by 0.34% and 2.82% respectively. Noticeably, average precipitation rose by 65.21% (21.62mm). These shifts highlight distinct climatic trends between the two periods.

The annual trends of energy consumption reveal intriguing patterns across various building archetypes. All archetypes had increasing trends for cooling energy consumption from 1990-2024, 1990-2004, 2005-2019, 2010-2024, as well as in the 26-year period of 1990-2015 still in widespread use for building simulations despite the significantly warmer subsequent decade. In contrast, heating energy consumption followed an opposite pattern with various situations: decreasing trends for all archetypes in the 2010-2024 period, but increasing in several cases:

• 3-storey office: Increasing from 1990–2004, 2005–2019, 1990–2015 and 1990–2024.
• 10-storey office: Increasing from 1990–2004, 2005–2019 and 1990–2015.
• Supermarket: Increasing from 2005–2019 only.

These trends are indicative of a changed climate and highlight the importance of using relevant climate files from the more recent 2010-2024 period in building energy simulations rather than the older ISMY data.