Combating climate change across Australia
October 25, 2021
Our team is helping our clients navigate through the environmental approvals process. Here¡¯s how
When it comes to climate, Australia can be a harsh place. It is the world¡¯s second-most arid continent after Antarctica, with more than a third of the land classified as arid and three quarters classified as semi-arid. More than 80% of the continent has at least three?months of the year without any rainfall. Yet, this vast continent contains other climate regimes ranging from tropical and monsoonal to temperate and alpine. As you can see, the climatic diversity of Australia is complicated.
Nevertheless, across this diverse climatic mosaic, evidence of climate change is apparent. Australia¡¯s continental average temperature increased 0.9¡ãC from 1910 to 1999, consistent with global trends. Over the last 50 years, some parts of the continent have warmed 1.5 to 2.0¡ãC, with minimum temperatures increasing more rapidly than maximum temperatures. While the number of days with frost has decreased, the number of extreme hot days has increased. Additionally, sea levels at monitoring sites around Australia have risen by approximately 1.2?millimeters per year from 1920 to 2000.
Geographic patterns of rainfall have also changed substantially over the past 50?years. Rainfall is increasing in many northern tropical areas but decreasing in many southwest and southeast temperate areas. More noticeably, the frequency and intensity of extreme rainfall-related events such as tropical cyclones and floods¡ªor the lack of rainfall resulting in droughts and fires¡ªhave also increased.
If we have recognized all these changes occurring over the last 100+ years, what can we do to combat climate change through the next century and beyond?
Large areas of southern Australia may experience substantial decreases in rainfall, leading to droughts and fires.
Tracking data to project future climate scenarios
Based on mid-range greenhouse gas (GHG) emissions scenarios, Australia¡¯s annual average temperatures are projected to be about 1¡ãC higher than today by 2030. Inland areas will warm more than in the coastal areas. The spring and summer seasons are expected to warm more than autumn and winter. If these trends continue, by 2070 Australia would be an average 1.8¡ãC warmer under the low-emissions scenario but could be as high as 3.4¡ãC warmer under the high-emissions scenario. Ocean warming could also see an increase of water temperatures up to 0.9¡ãC in the southern Tasman Sea and off the northwest coast and up to 0.6¡ãC elsewhere around Australia.
Compared to the projections for temperature change, predicted changes in rainfall are more uncertain. Overall, large areas of southern Australia may experience substantial decreases in rainfall. This will result in prolonged droughts, correlating to a decrease in runoff, river flows, and soil moisture content in most regions. In line with recent trends, the unpredictability of intensive rainfall events is also likely to increase in the future, along with the frequency of extreme weather events and the intensification of the El Ni?o¨CSouthern Oscillation phenomenon.
Although not exact, these projections give us valuable insight into planning for the future. Let¡¯s look at how this knowledge is guiding environmental approvals for projects in the energy and resources industry.
In line with recent trends, the unpredictability of intensive rainfall events is likely to increase in the future, along with the frequency of extreme weather events.
Climate planning: Environmental approvals for energy and resources
Climate change is becoming more important when assessing the impact of proposed developments in Australia. Our regulators are increasingly expecting companies to address sustainability matters¡ªincluding climate change¡ªas a consideration in environmental approvals. Most jurisdictions are committing to achieving net zero carbon emissions by 2050. Our Approvals Team here in Perth engages with these matters daily, as many clients now need GHG Management Plans that detail how they will assist in achieving the Western Australian government¡¯s stated goal of net zero.
These GHG plans must include predictions of emissions over time and a clear plan of how processes and technology are going to be used to reach their goals. That¡¯s where our team comes in. We advise our clients on the options available to meet regulatory requirements, satisfy regulators, and secure environmental approvals. These options include:
- Replacing processing components with up to date and environmentally friendly technologies and infrastructure
- Mine planning to increase efficiency
- Reducing vehicle movements
- Transitioning to electric vehicles
- Increasing the use of renewable energy, particularly in remote areas
- Increasing the purchasing of offsets
We know that combating climate change will be challenging. But it is possible if we all work together.
However, when assessing the impact of a proposal on the environment, it is not only project¡¯s GHG emissions that are important. We need to account for climate change in relation to project impacts in predicted scenarios and if these impacts will go up or down. This is particularly relevant for projects where water abstraction or dewatering is required.
Let¡¯s look at a case study below.?
Major flood events lead to a decrease in surface water salinity and provide a cue for hatching of aquatic invertebrates, which are a food source for waterbirds.
Putting our plans to work: A case study at Lake Mackay
One of our clients here in Australia¡ªAgrimin Limited¡ªis proposing to extract potash brine lake sediments on Western Australia¡¯s largest salt lake. Lake Mackay is about 450?kilometers south of Halls Creek, spanning across the border into the Northern Territory. The lake is dry for most of the year, but substantial rainfall events over the wet season may cause flooding that triggers boom cycles. This corresponds to the emergence of aquatic biota¡ªorganisms that live in or on water¡ªwith high productivity. This naturally attracts a significant number of waterbirds (including migratory species) for foraging and breeding.
These major flood events are important. Why? Because they lead to a decrease in surface water salinity and provide a cue for hatching of aquatic invertebrates, which are a food source for waterbirds. How these inundation events would change under an operational scenario¡ªas well as the influence of climate change¡ªwas largely unknown, with limited rainfall and inundation records due to the remote location of the lake.
To address these knowledge gaps, our team devised an innovative approach to analyze historic satellite imagery of the lake. This would help us identify the duration and extent of inundation events. We developed a customized script to automatically scan satellite imagery that was available since 1987. This data was then examined on Open Data Cube¡ªan open-source geospatial data management and analysis platform¡ªto quantify the timing and cover of inundation events on the lake. Next, we used GoldSim, a probabilistic simulation software package. GoldSim helped us to predict how the abstraction of brine from the lake may affect the hydrological regime under predicted future climatic change.
The outcomes of this work? We were able to objectively show the change in the number and duration of inundation events under different operational and climate change scenarios. Ultimately, our findings were enough to support the submission of environmental approvals documentation.?
We all have a role to play in climate advocacy¡ªit¡¯s not just related to the energy and resources industry.
Working together for climate advocacy
We know that combating climate change is challenging. But it is possible if we all work together. We all have a role to play in climate advocacy¡ªit¡¯s not just related to the energy and resources industry. Our buildings, water, and infrastructure industries need to be adapting to climate change as well. And you better believe our team will be there to help.?