The Intergovernmental Panel on Climate Change (IPCC) released a report recently entitled Global Warming of 1.5oC. The report describes how the impacts from warming of 2.0o C will be much more severe than the impacts from warming of 1.5o C. The response from Scott Morrison and the Liberal Party in Australia has been to reject the report's credibility and importance. This has led to promises to substantially increase greenhouse gas reduction targets from the Labor party and the Greens. In America Donald Trump has said he "will be looking at" the report. His critics say this is simply a stalling strategy in the hopes that other news events will overtake the IPCC report and he can continue to do nothing about global warming.
All this attention to the report is probably somewhat misplaced, though. The truth is that we are likely to experience most of the IPCC's list of impacts regardless of whether we radically cut our carbon emissions or not (although the impacts will be worse if we don't cut our emissions). And before the deniers get revved up, the reason is NOT because global warming isn't man-made or because global warming is unstoppable anyway. The reason is that we are damaging the global environment in hundreds of other ways, that are just as serious as the increase in greenhouse gases in the atmosphere.
Global warming is the environmental issue that dominates the media and political landscape, but without stabilisation of population, more efficient utilisation of resources and reduction of pollution most of the same impacts are still going to happen. Global warming is just one of the ways we are damaging our future way of life. Global warming isn't even the most important factor in several of the impacts that the IPCC identifies in its report. When the likelihood of so many environmental impacts occurring regardless of our policy responses to global warming, there should be some reconsideration of Australia's overall environmental policy agenda.
Advertisement
The IPCC report is a whopper to get your head around, but the space here is limited. As a compromise the Summary for Policy Makers (SPM) has been chosen as an easy enough document to access the findings of the report while still including enough detail so that it can be compared with the other impacts that we are inflicting on ourselves.
Biodiversity
Section B3.1 of the SPM makes the following statement:
Of 105,000 species studied, 6% of insects, 8% of plants and 4% of vertebrates are projected to lose over half of their climatically determined geographic range for global warming of 1.5°C, compared with 18% of insects, 16% of plants and 8% of vertebrates for global warming of 2°C (medium confidence).
Losing half of an organism's geographical range means more organisms crammed into less space, which means die-off of many organisms and some extinctions. The World Wildlife Fund Living Planet Report using 14,000 monitored populations of vertebrates concluded that just between 1970 and 2012 the population abundance had decreased by 58% and was likely to decline by 67% by 2020. The Living Planet Report lists climate change as the fifth most important threat to wildlife decline after habitat loss and degradation, species overexploitation (overfishing and poaching), pollution and invasive species and disease. Habitat loss, species overexploitation and pollution are likely to increase as quickly as climate change with rising population, so these factors are much more likely to bring reductions in species numbers than global warming.
Section B4.2 of the SPM makes the following statement:
Advertisement
Global warming of 1.5°C is projected to shift the ranges of many marine species, to higher latitudes as well as increase the amount of damage to many ecosystems. It is also expected to drive the loss of coastal resources, and reduce the productivity of fisheries and aquaculture (especially at low latitudes). The risks of climate-induced impacts are projected to be higher at 2°C than those at global warming of 1.5°C (high confidence).
Similar to the terrestrial ecosystems, the World Wildlife Fund (WWF) and National Geographic list unsustainable fishing, inadequate protection of marine areas, tourism and development, shipping, oil and gas drilling, water pollution, air pollution and aquaculture along with climate change as significant threats to ocean ecosystems.
In summary: plants, animals and oceans are stuffed regardless of how we handle greenhouse emissions.
Water stress
Section B5.4 of the SPM makes the following statement:
Depending on future socioeconomic conditions, limiting global warming to 1.5°C, compared to 2°C, may reduce the proportion of the world population exposed to a climate-change induced increase in water stress by up to 50%, although there is considerable variability between regions (medium confidence).
With respect to Water Stress, the IPCC concedes that socioeconomic conditions are at least as important as global warming. MIT researchers concluded that by 2050 "52 percent of the world's projected 9.7 billion people will live in water-stressed regions." The study found population and economic growth are the socioeconomic factors most responsible for increased water stress, resulting in an additional 1.8 billion people living in water-stressed areas.
Groundwater resources are being depleted much faster than they are being recharged in several arid areas of the world. This will cause additional water stress that is only marginally related to global warming, but substantially related to population growth and economic development.
The United Nations World Water Development Report makes similar conclusions to the MIT researchers.
Audrey Azoulay, the director-general of Unesco, noted "two-thirds of the world's forests and wetlands have been lost since the turn of the 20th century – a trend that needs to be addressed." "We all know that water scarcity can lead to civil unrest, mass migration and even to conflict within and between countries," she said. "Ensuring the sustainable use of the planet's resources is vital for ensuring long-term peace and prosperity."
The sustainable use of the planet's resources will still need to be done, even if we somehow stopped all greenhouse gas generation.
Crop yields
Section B5.3 of the SPM makes the following statement:
Limiting warming to 1.5°C, compared with 2.0oC, is projected to result in smaller net reductions in yields of maize, rice, wheat, and potentially other cereal crops, particularly in subSaharan Africa, Southeast Asia, and Central and South America; and in the CO2 dependent, nutritional quality of rice and wheat (high confidence). Reductions in projected food availability are larger at 2.0oC than at 1.5°C of global warming in the Sahel, southern Africa, the Mediterranean, central Europe, and the Amazon (medium confidence). Livestock are projected to be adversely affected with rising temperatures, depending on the extent of changes in feed quality, spread of diseases, and water resource availability (high confidence).
About 70% of the world's freshwater is used for irrigation, 20% for industry and 10% for residential, so it is clear that the future water stress will also impact crop yields. This is especially true in less developed countries where 90% of freshwater resources are used for agriculture. By 2050, agriculture will need to produce 60% more food globally, and 100% more in developing countries. These are stresses due to population growth not global warming. Crop Yields are also severely impacted by soil degradation which is not caused by global warming (but does worsen global warming). Increased population pressures make it likely that soil degradation will continue.
Certainty in Australian policy responses
The big difference with many environmental impacts and global warming is that we can insulate ourselves against many of these problems by stabilising our population, while efficiently managing our resource use and pollution. We can't do that with global warming. China's and India's coal fired power plants will warm up Australia and cause an increase in droughts and typhoons in Australia regardless of the policy decisions we make. China's and India's coal fired power plants will NOT destroy wild animal habitat in Australia, though. We probably can't save the rhino, elephant and tiger but we can save the koala and the wombat.
We might not be able to save the fisheries in the North Atlantic and the Mediterranean, but it is certainly in our power to save the fisheries off our coasts. We can ensure that the oceans around Australia are not overfished. We can limit polluted runoff from our coasts and preserve mangroves and wetlands in Australia even if they won't be preserved in the rest of the world. There is probably very little we can do about over-pumping groundwater in Saudi Arabia, but the Saudi's can't make us deplete our own groundwater. We might not be able to reduce soil erosion in Africa, but the African's can't force us to farm our land unsustainably. These factors make Australian environmental protection policy much more certain of success than our efforts to combat global warming.
The second difference is we don't have to wonder whether increased population, increased resource use and increased pollution will have the impacts that are being predicted. We know they will because they are already happening. Global warming impacts are also already occurring but the most serious of these are harder to quantify. Climate Scientists are not certain how much more destructive hurricanes will be, or how much drier droughts will be due to global warming.
It is absolutely certain, though, that with a billion more people to feed in 2030 and 2.2 billion more people in 2050 that the world will need more food, energy, minerals, land and water. Based on recent history it is also extremely likely that there will be more pollution, less forests and more refugees. When the worst-case scenarios are considered there are likely to be more violent conflicts within and between countries.
Two of the biggest obstacles against any unified effort to develop policies to combat global warming are the fear that others won't be doing their part and that the impacts are hard to pin down. Opponents of action against global warming and environmental protection in general, focus on these negatives and argue for business-as-usual. Business-as-usual will result in environmental impacts that are certain to reduce the standard of living of most of the world's population and will probably result in violent conflicts in many environmentally stressed locations around the world.
That's not a world we should leave our children. Australia can't solve all the world's environmental problems by ourselves and that shouldn't be our goal. What we can do is make sure that our little patch of the earth is run sustainably. A bonus of policy improvements like stable population, sustainable land management and protecting the oceans is that they will help combat global warming. They won't be sufficient to meet our goals on their own, but they will provide a significant addition. No single policy will solve our environmental problems but if we keep making these significant additions we can give our children a future that they can work with, rather than the one we are currently headed for.