Right: In May, 2021, the Federal Court of Australia ruled that environment minister Sussan Ley has a legal duty of care to safeguard Australian children and teenagers, as well as the environment, from the impacts of climate change, including that the minister must consider the 'avoidance of personal injury' when deciding whether to approve future mining projects.
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Background information
The information below has been abbreviated from the Wikipedia entry titled 'Climate change'. The full text can be accessed at
Climate change
Since the mid-20th century, humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.
The largest driver of warming is the emission of gases that create a greenhouse effect, of which more than 90 percent are carbon dioxide (CO2) and methane. Fossil fuel burning (coal, oil, and natural gas) for energy consumption is the main source of these emissions, with additional contributions from agriculture, deforestation, and manufacturing. The human cause of climate change is not disputed by any scientific body of national or international standing. Temperature rise is accelerated or tempered by climate feedbacks, such as loss of sunlight-reflecting snow and ice cover, increased water vapour (a greenhouse gas itself), and changes to land and ocean carbon sinks.
While locations of warming vary, the patterns are independent of where greenhouse gases are emitted, because the gases persist long enough to diffuse across the planet. Since the pre-industrial period, global average land temperatures have increased almost twice as fast as global average surface temperatures. This is because of the larger heat capacity of oceans, and because oceans lose more heat by evaporation. Over 90 percent of the additional energy in the climate system over the last 50 years has been stored in the ocean, with the remainder warming the atmosphere, melting ice, and warming the continents. The Northern Hemisphere and the North Pole have warmed much faster than the South Pole and Southern Hemisphere.
Impact on wildlife
Recent warming has driven many terrestrial and freshwater species poleward and towards higher altitudes. Higher atmospheric CO2 levels and an extended growing season have resulted in global greening, whereas heatwaves and drought have reduced ecosystem productivity in some regions. The future balance of these opposing effects is unclear. Climate change has contributed to the expansion of drier climate zones, such as the expansion of deserts in the subtropics. The size and speed of global warming are making abrupt changes in ecosystems more likely. Overall, it is expected that climate change will result in the extinction of many species.
The oceans have heated more slowly than the land, but plants and animals in the ocean have migrated towards the colder poles faster than species on land. Just as on land, heat waves in the ocean occur more frequently due to climate change, with harmful effects found on a wide range of organisms such as corals, kelp, and seabirds. Ocean acidification is impacting organisms who produce shells and skeletons, such as mussels and barnacles, and coral reefs; coral reefs have seen extensive bleaching after heat waves. Harmful algae bloom enhanced by climate change and eutrophication cause anoxia, disruption of food webs, and massive large-scale mortality of marine life. Coastal ecosystems are under particular stress, with almost half of wetlands having disappeared because of climate change and other human impacts.
Impact on human life
Health impacts include both the direct effects of extreme weather, leading to injury and loss of life, as well as indirect effects, such as undernutrition brought on by crop failures.[176] Various infectious diseases are more easily transmitted in a warmer climate, such as dengue fever, which affects children most severely, and malaria. Young children are the most vulnerable to food shortages, and together with older people, to extreme heat. The World Health Organization (WHO) has estimated that between 2030 and 2050, climate change is expected to cause approximately 250,000 additional deaths per year from heat exposure in elderly people, increases in diarrheal disease, malaria, dengue, coastal flooding, and childhood undernutrition. Over 500,000 additional adult deaths are projected yearly by 2050 due to reductions in food availability and quality. Other major health risks associated with climate change include air and water quality. The WHO has classified human impacts from climate change as the greatest threat to global health in the 21st century.
Climate change is affecting food security and has caused a reduction in global mean yields of maize, wheat, and soybeans between 1981 and 2010. Up to an additional 183 million people worldwide, particularly those with lower incomes, are at risk of hunger because of these impacts. The effects of warming on the oceans impact fish stocks, with a global decline in the maximum catch potential. Only polar stocks are showing an increased potential. Regions dependent on glacier water, regions that are already dry, and small islands are at increased risk of water stress due to climate change.
Most of the severe impacts are expected in sub-Saharan Africa and South-East Asia, where existing poverty is already exacerbated. The World Bank estimates that climate change could drive over 120 million people into poverty by 2030. Current inequalities between men and women, between rich and poor, and between different ethnicities have been observed to worsen because of climate variability and climate change. An expert elicitation concluded that the role of climate change in armed conflict has been small compared to factors such as socio-economic inequality and state capabilities, but that future warming will bring increased risks.
Necessary reduction of greenhouse gases
Climate change impacts can be lessened by reducing greenhouse gas emissions and by enhancing sinks that absorb greenhouse gases from the atmosphere.
To limit global warming to less than 1.5 C with a high likelihood of success, global greenhouse gas emissions need to be net-zero by 2050, or by 2070 with a 2 C target.
This requires far-reaching, systemic changes on an unprecedented scale in energy, land, cities, transport, buildings, and industry. Scenarios that limit global warming to 1.5 C often describe reaching net negative emissions at some point. To make progress towards a goal of limiting warming to 2 C, the United Nations Environment Program estimates that, within the next decade, countries need to triple the reductions they have committed to in their current Paris Agreements; an even greater level of reduction is required to meet the 1.5 C goal.
International climate agreements
Nearly all countries in the world are parties to the 1994 United Nations Framework Convention on Climate Change (UNFCCC). The objective of the UNFCCC is to prevent dangerous human interference with the climate system. As stated in the convention, this requires that greenhouse gas concentrations be stabilised in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can be sustained.
The 1997 Kyoto Protocol extended the UNFCCC and included legally binding commitments for most developed countries to limit their emissions. During Kyoto Protocol negotiations, the G77 (representing developing countries) pushed for a mandate requiring developed countries to "[take] the lead" in reducing their emissions, since developed countries contributed most to the accumulation of greenhouse gases in the atmosphere, and since per-capita emissions were still relatively low in developing countries and emissions of developing countries would grow to meet their development needs.
In 2015 all UN countries negotiated the Paris Agreement, which aims to keep global warming well below 1.5 C and contains an aspirational goal of keeping warming under 1.5 C. The agreement replaced the Kyoto Protocol. Unlike Kyoto, no binding emission targets were set in the Paris Agreement. Instead, the procedure of regularly setting ever more ambitious goals and reevaluating these goals every five years has been made binding. The Paris Agreement reiterated that developing countries must be financially supported. As of February 2021, 194 states and the European Union have signed the treaty, and 188 states and the EU have ratified or acceded to the agreement.