Week 7: Information series for the State of the Marine and Coastal Environment 2021 Report

The Commissioner for Environmental Sustainability is exploring the themes from Victoria’s first State of the Marine and Coastal Environment 2021 Report, over nine weeks.

For the seventh week of our information series, we take a closer look at the report’s climate and climate change theme.

As reported in Australia’s State of the Environment 2021 Report released this week Australia’s climate, along with the global climate, is changing due to human-induced climate change. Climate change is also having a high impact on the variability of our climate. We are already experiencing increased temperatures, changed rainfall patterns, increased extreme bushfire weather, and changed frequency and severity of extreme events such as heatwaves. These changes are having a profound effect on all aspects of our environment.

Victoria’s climate has changed in recent decades, becoming warmer and drier, and this is expected to continue. The report shines a light on the health of our marine and coastal environments to inform investment in marine and coastal science. It reinforces the need for a catchment to reefs approach to our policy and program interventions to protect and improve Victoria’s coastal and marine environments.

Dr Gillian Sparkes AM said, “Our report explores climate impacts in a marine and coastal context from sea level rise, coastal erosion, air temperature, marine heatwaves to rainfall. None of the climate and climate change impacts indicators were assessed as having a good status. Deteriorating trends were observed for 21 of the 22 regional indicators where the trend was assessed.”

Sea-level rise is one of the biggest threats associated with climate change to coastal areas. The report identified research that studied the shoreline position of the Victorian coast. This shows significant changes in 13% of the Victorian coast between 1986 and 2017, and it is estimated that erosion hotspots extend over 76.6 kilometres of the coastline. This is equivalent to about 6.2% of the Victorian coast.

In 2017, an erosion vulnerability assessment focused on the Gippsland coastline rated more than 100 kilometres of this coastline as having a very high vulnerability to coastal erosion.  This means that more than a quarter of the entire Victorian coastline most at risk to erosion is located along the Gippsland Lakes.

Victoria’s climate has been warming since the 1950s, with the scale of the warming more pronounced this century. Areas of the Port Phillip Bay coastline now regularly experience years with temperatures about 1.5 degrees warmer than an indicative pre-industrial era baseline. Read our report or visit our interpretive website to learn about what average temperatures in Victoria are projected to be by 2050s.

In recent years, marine heatwaves have increased in frequency around Australia. This has caused permanent impacts on marine ecosystem health, marine habitats and species. In 2019, an international study identified the ocean off southeast Australia as being particularly vulnerable to marine heatwaves.

Rainfall places fluctuating pressure on the water resources and agricultural sectors. We are experiencing wetter years interspersing a predominately drying climate. Rainfall reduction during the cool seasons can adversely impact stream flows and reduce reliability for water storage filling seasons. Notably, the biggest percentage rainfall reductions have occurred on the western side of Port Phillip Bay. This area is projected to have faster population growth in coming decades, placing increasing pressure on water resources.

Read the climate change chapter in the State of the Marine and Coastal Environment 2021 Report and view the interpretive website.

Next week’s theme is biodiversity. Keep following the information series to learn more.

More information

Type: Campaign
Category: Climate change
Tags: Environment