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Public Engagement

Public Engagement Document

Chapter 1 - Why Can’t We Ignore Climate Change?

What’s The Big Deal If Our Climate Is Changing?

1.1 Many scientists have warned that climate change would lead to irreversible consequences to the world. Recently, students around the world were out on strikes to protest and demand actions on climate change. Nevertheless, some skeptics choose to disregard the projected impacts of climate change as scaremongering; some consider receding glaciers and habitat loss for polar bears of little relevance. They have been indifferent to climate change impacts, not to mention changing lifestyles to cope with it. In fact, the impacts of climate change are hitting increasingly close to home. From erratic weather patterns to the rising frequency of extreme events, all of us should be able to experience that climate change is already affecting every part of our lives, no one is spared.

1.2 Our lifestyles and consumption habits cause the rising temperatures globally. Therefore, all human beings need to bear the responsibilities for mitigating the impacts of climate change. According to the recent Special Report on Global Warming of 1.5°C of the Intergovernmental Panel on Climate Change (IPCC), it is evident that human-induced warming has already reached about 1°C above pre-industrial levels, and the warming rate is now about 0.2°C per decade. 1 Temperatures greater than the global average has also already been experienced in many regions and seasons. Also, according to the Global Risks Report 2018 published by the World Economic Forum, extreme weather events such as storm surges, droughts and natural disasters have been identified as the top risks that pose a serious threat to global stability. 2

1.3 Globally, annual emissions of carbon dioxide (CO2) have risen dramatically over the past decades. With more CO2 accumulated in the atmosphere, the atmosphere traps more thermal energy on the Earth. The more carbon we pump into the atmosphere, the higher the average temperature of the planet will be, and we expect to see more frequent extreme weather events causing sustained and serious impacts on health, the economy and the environment.

Global Temperature Change Chart
Source: NASA3

Carbon Emissions

Carbon emissions are sometimes used as a shorthand for referring to the emissions of CO2, or greenhouse gases (GHGs) in general. Strictly speaking, gases that absorb and trap heat on the planet are called GHGs. The main GHGs in the Earth’s atmosphere are CO2, methane (CH4), nitrous oxide (N2O) and ozone (O3).

CO2 is the most common GHGs emitted by human activities, in terms of the quantity released and the overall impact on global warming. They are mainly produced from the activities that involve the burning of fossil fuels (e.g. coal and natural gas), including electricity generation, travelling by car, ship and plane, etc. To facilitate the measurement and comparison, the emissions of different GHGs are converted to CO2-equivalent (CO2e)* based on GHG’s global warming potential.

Note: *CO2-equivalent (CO2e): A metric measure used to compare the emissions from various GHGs based upon their global warming potential (GWP). The CO2e for a gas is derived by multiplying the tonnes of the gas by the associated GWP.

We Simply Don’t Have Time

1.4 Scientists have warned that we have some 10 years left to limit climate change catastrophe. According to the special report published by the IPCC in October 2018, the projected climate change impacts are substantially worse at 2°C compared with 1.5°C. Meanwhile, it is necessary to acknowledge that achieving the 2°C target of the Paris Agreement is indeed challenging. The key issue will be on the discussion of how to meet the target through the more aggressive proposals and its feasibility. 4

1.5 Like other coastal cities, Hong Kong faces multiple climate-related threats, including rising temperatures and more extreme weather phenonmena such as violent storms and flooding rains. Unless the world takes bolder and swift actions to reduce GHG emissions, these intensifying impacts are expected to take place at an even more rapid pace in the coming decades. Hong Kong, as a responsible member of the global community, is taking proactive steps to combat climate change.

Projections for 2100
Global Average Temperature Rise
Extreme Heat
Global population exposed to severe heat at least once every 5 years
increase 14%
increase 37%
Sea Level Rise
Contribution to sea level rise by 2100
increase 0.4 Metre
increase 0.46 Metre
Plant Species Loss
Plants that lose at least half of their range
decrease 8%
decrease 16%
Crop Yields
Reduction in maize harvests in tropical areas
decrease 3%
decrease 7%
Decline in marine fisheries
decrease 1.5 Million Tonnes
decrease 3 Million Tonnes
Coral Reefs
Further decline in coral reefs
decrease 70-90%
decrease 99%
Source: IPCC

Hong Kong Is Not Immune To Climate Change

More very hot days and hot nights

Over the past hundred years, the annual number of very hot days and hot nights in Hong Kong has increased from 2.2 to 15.7 and from 0.6 to 21.8 respectively. Under the high GHG concentration scenario, it is expected that the number of hot nights will add up to nearly 3 months by the middle of this century, and increase to about 5 months by the end of this century. 5

Annual number of heavy rain days increases

Days with hourly rainfall more than 30 mm increased at an average rate of 0.2 days per decade from 1947 to 2018 in Hong Kong. Under the high GHG concentration scenario, the projected annual maximum 3-day rainfall will increase by about 40% at the end of this century. 6

Fewer rain days but average rainfall intensity increases

Extreme precipitation events have become more frequent. The hourly rainfall record at the Hong Kong Observatory headquarters was broken several times in the past decades. The current hourly rainfall record was 145.5 mm in 2018 at the Hong Kong Observatory headquarters.7

Rise in sea level

On average, the mean sea level in Victoria Harbour went up 31 mm per decade during 1954-2018. It is expected that extreme sea level events that are rare today will become more frequent at the end of this century. 8

Increase in storm surge threat

Only between 2017 and 2018, there were two super typhoons necessitating the issuance of the Hurricane Signal No. 10, both with significant storm surges. 9

If you still remember……. this is not a movie scene!

Storm surge induced by Super Typhoon Hato in 2017 and Super Typhoon Mangkhut in 2018 caused flooding across various districts
Storm surge induced by Super Typhoon Hato in 2017 and Super Typhoon Mangkhut in 2018 caused flooding across various districts

Mitigating Climate Change For Survival and Well-beings Of Our Current and Future Generations

What Can We Benefit From Climate Change Mitigation?
Better health and less premature deaths
  • Researchers found that dramatic cuts in global GHG emissions could help prevent 300,000 to 700,000 premature deaths annually by the year 2030.10
  • A study published on Hong Kong Medical Journal in 2018 indicated that as the global warming worsened, the number of city dwellers suffering from allergic diseases has risen by three to five fold in recent decades. 11
Creating employment opportunities and green growth
  • A recent report by Stern and other authors highlighted the opportunities arising from ambitious climate mitigation actions in five key economic systems—energy, cities, food and land use, water, and industry—that can drive growth and meet the development objectives. It also reported that transitioning to the low-carbon, sustainable growth path could deliver a direct economic gain (US $26 trillion) by 2030 compared with business-as-usual, generate over 65 million new low-carbon jobs in 2030. 12
Business prospects
  • For individual business, one of the major benefits of reducing GHG emissions is to save costs through more efficient use of resources, particularly energy, that cut utility bills. Besides, companies taking ambitious climate actions could enhance their reputation amongst stakeholders and thus foster business development. For the business sector, mitigating climate change could create new business opportunities in new and emerging markets such as in the clean energy sector. It may also reduce risks and costs of damage to assets as a result of extreme weather events.
Costs Of Inaction Are Terrifying
Damage to infrastructure; economic loss
  • The Super Typhoons Hato and Mangkhut slammed Hong Kong in 2017 and 2018 respectively and caused massive damage, including flooding in many coastal and low-lying areas, huge amount of fallen trees, suspension of the public transport, and interruptions of the water and power supply. Under climate change, the number of super typhoons are also expected to increase. 13
Unstable water supply
  • A study conducted jointly by researchers at CUHK and the Commonwealth Scientific and Industrial Research Organisation in Australia suggested that the continued growth in GHG emissions throughout this century could bring about more frequent and intensive floods and droughts in the Pearl River Basin in the last three decades of this century. 14
Instability of crop production; rising food prices
  • Researchers from the Earth System Science Programme at CUHK predicted that the rise in temperature would reduce global food production by more than 10% and increase undernourishment rates by more than 30%.15

Global Response To Climate Change

Climate Actions: The Three Main Concepts

To prevent or minimise the damage already or may be potentially caused by climate change by strengthening our ‘infrastructure’; including energy, water resources, buildings, coastal facilities, transport, emergency services, health, food, finance, and communication.


To reduce or prevent GHG emissions for alleviating effects of climate change such as heat waves and droughts, extreme storms, pressure on water resources and crop yields, damage to corals, sea level rise etc.


To maintain functionality of the society under the inevitable effects of climate change; cope with and dampen climate-related stresses; and maintain public services, economic and social activities.

Climate Actions: The Three Main Concepts

Absolute Carbon Emissions VS Carbon Intensity

Carbon intensity is the volume of emissions per unit of GDP. Reducing carbon intensity means that less carbon emissions are being produced per unit of economic output. In the past, if GDP grows so do the total emissions. But taking advantages of the reduction in technology cost, enhanced awareness about climate change, etc., there are signs of marked decoupling of emissions and economic growth.

A more concrete measure of carbon emissions reduction is “absolute reduction”, meaning the reduction in the total emissions. To mitigate climate change, total emissions must be decreased in the long run.

Carbon Emissions Per Capita

Meanwhile, looking at the total carbon emissions alone does not tell the full story of a city’s contribution to global warming.

A more useful measurement is carbon emissions per capita (person). Under this measurement, we can compare the CO2 per capita of different places around the world.

The Paris Agreement

1.6 Succeeding the Kyoto Protocol, the Paris Agreement* is an ambitious multilateral treaty agreed in December 2015 by 196 signatories with a view to combating climate change and taking actions towards a low-carbon, resilient and sustainable future. China formally signed it on Earth Day, 22 April 2016.

Every 5 years, all signatories must formulate their own “nationally determined contributions” (NDCs) with targets and timelines to be set

Limiting the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to within 1.5°C above pre-industrial levels

Note: *International shipping and aviation are not included in the Paris Agreement. International Maritime Organization and the International Civil Aviation Organization are responsible for carbon reduction of their respective sectors.

1.7 To limit the increase in the global average temperature to well below 2°C above pre-industrial levels, the world will need to reduce absolute carbon emissions between 40% to 70% by 2050 compared with 2010 and to achieve net zero emissions of CO2 and other GHGs before 2100. The recent Special Report on Global Warming of 1.5°C of the IPCC has provided scientific evidence that limiting warming to 1.5°C could further reduce climate risks compared with limiting it to 2°C. Yet, it is already an audacious plan to limit global warming to 2°C. To go further beyond to 1.5°C will require global carbon emissions reaching net zero around 2050.

Our Response to The Paris Agreement

1.8 The Paris Agreement came into force on 4 November 2016. As decided by the Central People’s Government, the Paris Agreement applies to the Hong Kong Special Administrative Region. We are obliged by 2020 to formulate a long-term decarbonisation strategy up to 2050. We are also obliged to review our climate change efforts every 5 years. As of now, we are on track to achieving the carbon intensity target of 65% to 70% by 2030 using 2005 as the base.

China’s NDC by 2030

  • To achieve the peaking of carbon dioxide emissions around 2030 and making best efforts to peak early
  • To lower carbon dioxide emissions per unit of GDP by 60% to 65% from the 2005 level
  • To increase the share of nonfossil fuels in primary energy consumption to around 20%
  • To increase the forest stock volume by around 4.5 billion cubic meters on the 2005 level
Hong Kong’s Carbon Emissions Reduction Measures by 2030

    • ‘Peak Carbon’ – local electricity generation is by far the biggest contributor to carbon emissions making up about 67%. Hong Kong’s emissions will peak in or before 2020 when we have more electricity generation from natural gas in our fuel mix.
    • Carbon Intensity and Absolute Reduction – our current decarbonisation path will help reduce the carbon intensity by around 50% by 2020. Our 2030 target would take us to 65% to 70% carbon intensity reduction from the 2005 level.16
    • Per capita carbon emissions – our per capita calculation is derived from dividing the total carbon emissions with the population, which works out to be around 5.7 tonnes in 2016. Our target is to reduce Hong Kong’s per capita carbon emissions to less than 4.5 tonnes by 2020; and further to about 3.3-3.8 tonnes by 2030.

The Public Engagement Process

1.9 Through this public engagement (PE) process, the Council for Sustainable Development hopes to arouse public awareness of the impact of carbon emissions, and gauge the views of the community in formulating Hong Kong’s long-term decarbonisation strategy, charting practical pathways and developing feasible actions to achieve that target, thereby contributing to the global decarbonisation efforts.

1.10 Given the long-term low greenhouse gas emission development strategies envisaged under the Paris Agreement only covers mitigation, this PE exercise will focus on gauging public views on mitigation actions* relating to reducing carbon emissions that suit the geographical, social and economic contexts of Hong Kong.

Objectives of the Public Engagement
Enhance Public Awareness

To raise awareness of the impact of carbon emissions and the serious consequences of inadequate actions to reduce carbon emissions.

Consensus Building and Recommendations

To seek public views on mitigation actions relating to reduction of carbon emissions bearing in mind the additional cost and behavioural changes required; and to promote community actions including changes in lifestyle and consumption behaviour to mitigate climate change.

Stakeholders Participation and Cooperation

To identify the roles of different stakeholders and foster collaboration opportunities among them and gauge their views on mitigation actions against climate change.

Note: *We have not included adaptation and resilience measures in the PE exercise because the timetable to complete the exercise is tight, and many of the measures are relatively technical and involve operational details. Besides, an interdepartmental Climate Change Working Group on Infrastructure has been formed to review the design standards and examine necessary measures for strengthening our infrastructure. The Contingency Plan on Natural Disasters is also being reviewed by Security Bureau.

Executive Summary Chapter 2
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