Climate change refers to long-term changes in the earth's weather, including changes in temperature, wind patterns and rainfall. Such changes are caused by a combination of both natural and human induced causes.
In particular, the burning of fossil fuels and deforestation are responsible for increases in ‘heat trapping’ greenhouse gases in the atmosphere, especially carbon dioxide.
Not a new concept
While climate change has been receiving a lot of attention over the last decade or so, it is not a new concept.
In fact, scientists have understood the relationship between the earth’s atmosphere and temperature (the greenhouse effect) since the mid-1800s.
What is the latest science telling us about climate change?
The earth’s climate has varied between ice ages and warm periods, corresponding with changes in the amount of carbon dioxide in the atmosphere.
There are two key things that are different about the warming that we are experiencing now:
- The rate of change has never been this fast before. Previously, the earth warmed (or cooled) over many thousands of years, however we have contributed to a very rapid change in only 150 years.
- The levels of carbon dioxide in the earth’s atmosphere have not been as high as they are now for at least 800,000 years. Scientists have measured the amount of carbon dioxide and methane frozen in Antarctic ice from as far back as 800,000 years and the current levels for both gases are unprecedented (Figure 2).
For an engaging explanation of climate science, watch the presentation by Professor Steve Turton from James Cook University (embedded on the right).
Across the world, thousands of scientists have been working hard for many years to understand the way weather patterns work and how they might change with more greenhouse gases in the atmosphere.
The result of this work is 46 complex computerised models (Global Climate Models), which all use our current understanding of climate physics to predict the changes in things like temperature, rainfall, humidity and sea level.
Their projections take into account the range of future greenhouse gas emissions scenarios.
Recently, scientists working for CSIRO and the Australian Bureau of Meteorology have refined these global climate models so that we have a clearer understanding of how climate is likely to change in our Wet Tropics region specifically.
This work has been done to assist regional bodies to incorporate information about climate change into their new NRM Plans.
This CSIRO and BOM work has also resulted in an exciting new website www.climatechangeinaustralia.gov.au which has both detailed information about climate change and interactive tools available to the public.
What will climate change mean for the Wet Tropics?
The actual amount of change we experience in our region will depend on how many greenhouse gases we continue to produce across the globe. In general:
- Temperatures in all areas of the region will be hotter and heatwaves will be more frequent, warmer and last for longer. The increase in temperatures will also make it hotter for animals and plants, including those living in the ocean and our waterways.
- Extreme rainfall events will be more intense, leading to more flooding, loss of soil and runoff of pollutants. It is not clear how annual and seasonal rainfall patterns will change but they will be less predictable.
- Sea levels will continue to increase, inundating low-lying coastal areas with sea water, especially during storm tides.
- Tropical cyclones are expected to be more intense although less frequent. Damage to homes, infrastructure, industry and natural areas is likely to be more severe and more widespread.
Click here for more details on the projected changes for the Wet Tropics region.
What can we do and how can we adapt?
Even if we reduce our production of greenhouse gases, they will remain at high levels in the atmosphere for some time to come. As a consequence, we are ‘locked in’ to some of the impacts of climate change, even if we make very deep cuts in our emissions today. These changes will fundamentally affect our communities, changing where we can live in our region, which industries will remain viable and our land management practices.
Planning the ways we can adapt to these changes will lead to better outcomes for our region, otherwise the alternative is to just wait until things get much worse, by which time we may have less chances to adapt successfully. Some of the changes necessary will be transformational, meaning that we will need to develop new ways of doing things and sometimes even do things completely differently.
Working together across industry sectors and involving researchers and all levels of government will help develop the knowledge and support required to make sensible changes within a reasonable time frame. We do not need to wait as we already have enough information to make better decisions that will help future-proof the Wet Tropics.
Key priorities for working on adaptation now include:
- Infrastructure, especially in coastal areas
- Water supply
- Coastlines, estuaries and wetlands and all other areas at risk of sea-level rise, storm surge and floods
- Agriculture and other climate-dependent industries such as tourism
- The natural environment, including biosecurity and invasive species
Scientists from James Cook University and CSIRO have worked with NRM groups in northern Australia to develop an understanding of potential options for adapting to a changing climate in the Wet Tropics region – Click here to access these documents.