HUMAN INDUCED CLIMATE CHANGE
Increases in greenhouse gases resulting from human activities have lead to a net effect of warming of the climate system leading to direct impacts including increased air and ocean temperatures, widespread melting of snow and ice and rising global average sea level.
“Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities since 1750.” — IPCC Climate Change 2007: The Physical Science Basis, Summary for Policy Makers. The increases in greenhouse gases can be attributed to fossil fuel use, land-use change and agriculture.
Climate Change Impacts on Western Port
The former Western Port Greenhouse Alliance (now SECCCA) worked with the Victorian Department of Sustainability and Environment (DSE) and the CSIRO to determine the impacts of climate change on the Western Port region. Below is a summary of projected changes.
Summary of projected climate changes for Western Port
- annual warming of 0.2 to 1.4°C by 2030 and 0.7 to 4.3°C by 2070
- day time maximum temperatures and night time minimum temperatures will rise at a similar rate
- warming will be similar throughout the seasons
- a 10 to 40% increase in the number of hot summer days (over 35°C) by 2030 and a 20 to 300% increase by 2070
- a substantial reduction in the number of frost days by 2030 and a possible loss of all frost days by 2070
- annual precipitation decreases likely (changes of +3 to -9% by 2030 and +9 to – 25% by 2070)
- extreme heavy rainfall events may become more intense
- droughts are likely to become more frequent and longer
- dry conditions that currently occur on average one in every four years may increase to up to one in three years by 2030
- due to hotter conditions, droughts are also likely to be become more intense
- increased evaporation rates
- drier soil likely, even if precipitation increases
- decreased average run-off in streams
- hotter, drier conditions likely to increase bushfire risk
- winds are likely to intensify in coastal regions of Victoria, particularly in winter as a result of more intense low pressure systems. Low pressure systems off the east coast of Australia may become more frequent
- sea level rise of 7 to 49cm by 2070