Challenge of Environmental Climate Change in Australia

Climate change presents a challenge to Australia’s water resources

There is so much global warming in the world today that is mainly caused by artificial activities. Impacts resulting from climate change are already being felt, and some will have consequences for centuries to come. Climate change in Australia, therefore, presents a challenge to water resources and the environment. In this article, we will explore the latest scientific thinking and research on challenges posed by climate change. Observed projections and changes relating to extreme events, ocean acidification, rainfall, and temperature are presented in the context of Australia. 

What is Climate Change

Climate change is the directional change in climate above the natural limit attributed to human activities that change the composition of the atmosphere. For instance, an increase in the burning of fossil fuels over the past 100 years has increased the level of Carbon dioxide (CO2). The same effect can be attributed to land clearing. The current CO2 concentration of 385 ppm (parts per million) is already 100 ppm higher than that witnessed during the pre-industrial period (Steffen 2006, 2009).

According to the 2007 report by Australia’s CSIRO and Bureau of Meteorology, Climate change in Australia: Technical report, global warming is beyond doubt as evidenced in the rise of sea level, increasing ocean acidity, accelerated melting of snow, increasing oceanic and atmospheric temperatures. 

It’s important to note that global warming can be slowed down by reducing greenhouse gas emissions. However, as things stand, it seems we’re locked in a period of unavoidable climate change for hundreds of years. According to studies, human-induced climate change will go on for at least 1000 years even after emissions cease. 

Landscape fragmentation is also adding to the vulnerability of natural systems to climate change/global warming. Fragmentation has proven to cause discontinuity and isolation of ecosystems and create artificial barriers which limit the migration, resilience, and dispersal of biota. 

Global warming is linked to changes in rainfall patterns which can adversely affect water supply for agriculture, ecosystems, and humans (Solomon et al. 2009). 

Climate Change Projections and Observed Changes

Several aspects of the environment have already been affected, and others are projected to be affected by climate change. 

Temperature

The annual temperatures in Australia are projected to rise in parallel with the rises in global average temperatures. However, there will be some major regional variation (Garnaut 2008). The average temperature increase for most parts of Australia has been 0.9°C since 1950. The frequency of cold days and nights has reduced while hot days and nights have increased (CSIRO & BoM 2007). 

The annual estimate of global warming in Australia by 2030 relative to 1990 is around 1.0°C under a situation of mid-range greenhouse gas emissions. It’s also predicted that there will be less warming during winter and in coastal areas. 

Rainfall

Since the 1950s, most of the south-western and south-eastern Australia has experienced a substantial decline in rainfall. The largest drying along the east coast exceeds 50 mm per decade. The last decade has also marked one of the most severe droughts in the history of Australia. 

On the contrary, there has been an increase in rainfall frequency and intensity in Central and North-western Australia over the same period. Generally, rainfall patterns in Australia have shown a continuous decline. The changes have been dominated by a highly significant and strong decline in autumn rainfall. 

Extreme Events

Apart from having affected rainfall patterns, it’s predicted that climate change could lead to increased frequency and intensity of extreme weather events, including droughts, floods, hail, severe storms, and tropical cyclones (CSIRO & BoM 2007). 

Ocean acidification

An increase in the level of carbon dioxide in the atmosphere has a significant effect on the ocean. All oceans in the world are experiencing a decline in their pH level, thus becoming more acidic. It’s a proven fact that most of the CO2 produced due to human activities is absorbed and stored in oceans. And when it dissolves in ocean water, it forms carbonic acid. 

Impacts of Climate Change in Australia

In addition to the general drying trend and warming, the intensity and frequency of extreme events will be a critical feature of climate change. In general, impacts of climate change are likely to subject Australia’s freshwater, terrestrial, oceanic, and coastal environments to potential damage and major changes. Being the driest inhabited continent and land of low productivity oceans and soils, Australia is highly vulnerable to the increased effects of climate change. 

Evidence shows that several of these changes are already taking place. It’s also on record that natural disasters have cost Australia billions of dollars each year. Climate change is likely to intensify water security problems by 2030. 

Water Resources and Climate Change

Australia is the driest inhabited continent globally, and for this reason, streamflow and rainfall are highly variable naturally. Most lowland rivers have some periods of flood and dry and often experience large floodplains with connected wetlands. For this reason, Southern rivers have been dammed to offer a reliable water supply for urban use and agriculture.

The Australian scarce water resources have been put under increasing pressure thanks to the conflicting demands of irrigated agriculture, biodiversity and conservation of ecosystem services, and urban supply. The situation is further worsened by a growing dependence on groundwater and drought. 

The future of climate generally projects a future warming and rainfall decrease that indicates a reduction in water supply and increase in demand. However, little is known about the impacts of groundwater. 

Runoff 

Increased potential evaporation and changes in rainfall are likely to cause reduced runoff across Australia. As a rule, if rainfall decreases by one percent, catchment runoff will decline by almost two or three percent (O’Neill 2008). A change in rainfall seasons has also had a significant effect on runoff (Potter & Chiew 2009). 

Adaptation and aquatic systems

Climate change has proven to have a critical and significant implication for Australia’s aquatic systems and water resources, including the ecosystem services they provide such as: 

• Provision of freshwater for irrigation, environmental, domestic supply, and others
• Provision of home for species of aesthetic, recreational, and commercial value including aquatic plants
• Flood mitigation
• Removal of nutrients, sediments, and other pollutants using riparian filtering

Several options can be employed to increase the resilience of aquatic systems to the impacts of climate change and include: 

• Reducing nutrient loading
• Maintaining riparian vegetation and forests
• Maintaining and restoring ecological flows
• Enhancing connectivity
• Minimizing the spread of weeds and pests
• Minimizing withdrawal of groundwater
• Minimizing threat of acid sulfate soils
• Assisting migration and dispersal through buffer zones and corridors
• Placement of new reservoirs strategically

Need to Act and Adapt

According to Nicholls, who is a leading climate expert, Australia needs to do the following four things to combat climate change:

• Improve the scientific understanding of climate drivers
• Adapt: build resilience and reduce vulnerability
• Monitor climate for change at the regional level
• Improving modeling capacity in Australia for predicting climate

Over the last five years, there has been an increase in knowledge of the impacts of climate change on Australia. There are, however, several approaches that have been suggested to achieve enhanced resilience for Australia’s biodiversity and include: 

• Minimizing or removing existing stressors
• Maintenance of well-functioning ecosystems such as marine, aquatic and terrestrial
• Developing appropriate seascape and landscape connectivity
• Protection and identification of refugia
• Eo-engineering
• Developing an effective monitoring network
• Flexible management and policy approaches
• Preservation of genetic stock such as seed-banks, zoos, etc
• Strong Australian and global emission mitigation action

There is no argument that the global and Australian benefits of action to prevent climate change will by far exceed the cost of lack of action. Therefore, the solution is for decision-makers in industry, the community, and government to come up with options for reducing climate change vulnerability. However, non-climate factors such as governance, institutional, social, technological, and economic conditions affect resilience and vulnerability. These factors need to be effectively studied. 

Conclusion

Climate change or global warming has shifted from being just a topic of scientific conversation to being part of our daily lives. It intensifies the need for a sustained and urgent increase in investment in our environment. Above all, there is a need for everyone to act and adapt to climate change in Australia and worldwide.