Notes for Climate change meeting May 22nd Peter Black and Gerald Oakham GLOBAL WARMING – THE PROBLEM A What is GW? (GO) 15 mins 1. The science behind our understanding of climate change is not simple. 2. This makes it hard to generate consensus on the action required. 3. So, let’s start with a summary of what is known. 4. In the past 2000 years global temperatures have been relatively stable - Show plot. 5. Industrial revolution led to extensive use of fossil fuels as well as population growth. 6. Following Industrial revolution mean global temperatures have risen dramatically – show plot 7. Brief description of notion of mean global temperature Measure above land and sea. 4 different data sets, need to fill in for missing areas. 8. Temperature increasers caused by production of greenhouse gasses by our industrial society. 9. Green houses trap heat (brief description) leading to temperature rises (CO2, methane + ?) 10. Temperature rise and CHG emissions correlated (plot of GHG rise and temp rise?) 11. Future trends are calculated using climate models that describe how the atmosphere and oceans (biosphere) responds to increasing heat. (This is the complicated part.) 12. Many Climate models (written by different groups) used to understand range of possible affects (Climate model – major piece of computer code) 13. Work coordinated by IPCC - International Panel on Climate Change UN body. 14. IPCC have used a number of scenarios to project how global temperatures will change 15. Scenarios make assumptions about how GHG emissions change and what is done to remove GHG from the atmosphere. 1
16. Scenarios range from optimistic ((8.5) concerted global action to reduce GHG emissions and use carbon capture) and pessimistic ((2.6) we carry on with business as usual) 17. Wild cards! - Tipping points 1) Melting of ice sheets 2) loss of permafrost – describe what this means. For now, assume we don’t pass one of these! 18. Show projected world temp increase for two scenarios plot 19. Show graphics of Canadian warming show plot 20. Also affects rainfall, example for Canada – show plot 21. Temperature increasers are not uniform – Show plot of Canada temp. rises 22. The science is clear, temperatures are increasing and will continue to increase – B What and who is causing it? (GO) 5-10 mins 1. Nearly all current human activities increase GHG in the atmosphere for example: - a. Heat and power production i. Oil, coal, gas problem ii. Hydro, solar, wind good iii. Nuclear also good b. Most transportation systems Electrification can be good depending on source of electricity Difficult to make low emission planes. c. Construction (Cement) i. Current process of using concrete a problem d. Agriculture i. Meat production biggest problem e. Deforestation i. “Easy” issue to fix but needs political will. 2. Show pie chart of contributions to Global warming 3. Contributions to GHG are made both by individuals (auto use, flights) and industry, petro chemicals heavy industry etc. 4. Control of the latter has to be done via govt. policy. 5. Will be discussed further after break C What harm has GW caused already? /What harm would 2 degree warming cause. (GO) 10+ mins 2
Global warming is already impacting live on the earth. Here are some of the ways:- 1. Acidification of ocean leading to coral bleaching (all over the world). 2. Mass extinction (Note loss of habitat is a big factor here) 3. Increase in sea level (due to higher water temperature and ice melt) So far 8 islands lost in Pacific ocean –not populated. 4. Loss of Arctic sea ice and loss of glacial ice. (Some water supplies depend on glaciers) 5. Increases in extreme weather events. Increased heating of atmosphere – larger transfer of heat from tropics to poles – higher winds and storms. Examples: a. River flooding Ottawa valley as example (complicated??) b. Coastal flooding (mainly in connection with hurricanes) c. droughts (dry conditions in west leading to increase in forest fires) d. fires e. More widespread and intense tornados (Severe summer storms caused Tornados in Ottawa in summer of 2018) f. Winter storms. Describe how global warming can lead to more snow! g. Increase in tropical storm energy Show plot Original goal was to limit temperature rises to 2.0 ° C degrees. In Paris agreement move to attempt to limit rise to 1.5 ° C. What are the differences? 1. Irreversible melting of ice in Antarctica or Greenland could be triggered between 1.5 ° C and 2.0 ° C degrees of warming leading to multi-meter rise over 100s to 1000s of years. (B2.2) 2. Limiting warming to 1.5 ° C results in slower sea level rise allowing for better adaptation to changes. 3. Insects, plants and animals will lose twice as much geographic range with 2.0 ° C compared to 1.5 ° C 4. Limiting global warming to 1.5 ° C rather than 2.0 ° C is projected to prevent the thawing over centuries of a permafrost area in the range of 1.5 to 2.5 million km 2 5. Ice free artic – once in 100 years for 1.5 ° C and once in 10 years for 2.0 ° C 6. Coral reefs will further decline by 80% for 1.5 ° C and 99% for 2.0 ° C 3
7. Poverty and disadvantage are expected to increase in some populations as global warming increases; limiting global warming to 1.5 C, compared with 2.0 ° C could reduce the number of people both exposed to climate-related risks and susceptible to poverty by up to several hundred million by 2050. 8. Above issue gives rise to migration attributable to Climate Change– will be a big political issue. 9. Most adaption needs will be lower for 1.5 ° C compared to 2.0 ° C For more details see the 1.5 ° C IPPC report. Health/coffee break 10:50 to 11:00 4
RESPONSES TO GLOBAL WARMING – MITIGATION D Government Action International Action 1. Almost a quarter of a century ago, in 1995, the United Nations established the United Nations Framework Convention on Climate Change (UNFCCC or UN Convention). Every year since then, a growing number of countries have participated in the annual UN Climate Change Conference to assess progress and reach agreements in dealing with climate change. Each gathering is called a Conference of the Parties or COP (hence COP 1, COP2, etc.). 2. The ultimate objective of the UN Convention is to stabilize atmospheric concentrations of GHGs at a level that would prevent dangerous human interference with the climate system. 3. Fifteen years later, in 2010, Parties to the UN Convention agreed that future global warming should be limited to less than 2.0 °C relative to its level before the Industrial Revolution. 4. But with the Paris Agreement of 2015 the Parties set a new target: to “do their best” to achieve warming below 1.5 °C. This was the first climate change agreement in which countries (197 of them) committed to taking action, demonstrating higher levels of global engagement and collaboration. 5. Paris Agreement – slide 15 6. The Intergovernmental Panel on Climate Change ( IPCC ), established in 1988, is a United Nations intergovernmental body supporting the work of the UN Convention. It provides an internationally accepted scientific authority on climate change, producing reports which have the agreement of leading climate scientists and the consensus of participating governments ( so, both scientists AND political representatives produce the reports). 7. Last year, In October 2018, the IPCC issued a report commissioned by the Parties - the IPCC Special Report on Global Warming. It stated that, even assuming full implementation of national plans set out in the Paris Agreement, net emissions from 5
2010 would continue to increase, leading to a warming of about 3 °C by 2100, and more afterwards. 8. The Report said that limiting warming below or close to 1.5 °C would require a decrease in net emissions from 2010 of about 45% by 2030 and net emissions of zero by 2050 (“net emissions” allows for both emissions into the atmosphere and activities to remove carbon from the atmosphere) Canadian Government Action 1. Canada is the ninth-largest emitter of greenhouse gases in the world, with one of the highest per capita emissions of all countries. 2. Since its first international agreement at the UN Climate Change Convention in 1992, Canada’s greenhouse gas emissions have increased by 100 megatonnes - over 15 % (from 620 to 720 in 2015). This increase occurred despite the federal government’s committing to several international agreements and developing a number of federal plans since 1992. See slide 16 - Cda’s GHG Emissions 1992- 2030 3. In 2016, Canada ratified the Paris Agreement . As its contribution to the Agreement, Canada committed to reducing emissions from their level in 2005 by 30 percent by 2030. (Note – Paris Agreement based on base year 2010 while Canada’s base is 2005). This would require a decrease of about 200 megatonnes, from about 700 megatonnes to 510 megatonnes. 4. If Canada decided to try to meet the IPCC’s recent recommendation, it would have to reduce its emissions by over 300 megatonnes - a 45% reduction from 720 to 385 megatonnes. 5. In December 2016, the federal government proclaimed The Pan-Canadian Framework on Clean Growth and Climate Change (Pan-Canadian Framework) which outlines federal and provincial measures to reduce greenhouse gas emissions. 6. Two years later, in December 2018, the government issued its Second Annual Report under the PCF, setting out federal and provincial initiatives (84 pages). Federal measures include: 6
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