Implications for dairy industry

 

The impact of increased greenhouse gas concentration in the atmosphere and on global warming can be seen through a number of indicators:

  • Air and ocean temperatures increased 0.7oC from 1906-2005

  • Only 5 of the ‘hotter than average years for Australia’ occurred before 1950, with a clearly rising temperature trend for the last 100 years

  • All years since 1990 have been hotter than average

  • An increase in extremely high and extremely low temperatures

  • Widespread melting of snow and ice, and a retreat of the world’s glaciers

  • Sea levels have risen 17cm since 1900.

By 2030, a 1-6°C temperature rise, above 1990 levels, is expected. Inland areas will experience the greatest level of warming, with coastal areas slightly less affected. To give an indication of the scale of these temperature rises, a 1°C rise would make Melbourne like Wagga Wagga in NSW, a 3°C rise like that of Sydney and a 6°C rise like that just north of Roma in Queensland.

Other global changes include:

  • Oceans becoming more acidic, as a result of absorbing more carbon dioxide, and sea-level rise

  • Shifts in the location of many plants and animals due to warming

  • More-intense rainfall, changes to runoff, more heatwaves, increase drought risk, more intense storms (with regional variations for all of these impacts)

  • An increase in water vapour in the atmosphere since at least 1980, consistent with the theory that warmer air holds more moisture.

While there is a growing consensus on the causes and likelihood of climate change, there is uncertainty about the impacts across the agricultural sector. Given that predictions are for a hotter, drier South and wetter North, the impacts will likely be complex, and vary by commodity and region.

Dairy farmers have already seen the impacts of climate change on their businesses:

  • In Gippsland & Northern Victoria, pasture growth patterns have changed, spring now starts about four weeks earlier.

  • In the Northern Irrigation Area, reduced water availability has favoured annual pastures over perennial pastures. Farmers are investigating pastures such as lucerne, which have deeper root systems and can tolerate longer periods of water deficiency.

  • In South Australia, in response to more competitive land and water use, as well as reduced availability and quality of water, some farmers are already making changes to their systems, while others are relocating.

Cow in field  Video: Climate change and dairy
See why reducing emissions intensity is important for dairy farmers
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