Climate Change

Climate change has reached a critical point. We need to make dramatic changes to how we build – today.


Buildings = 40% of Carbon Dioxide Emissions

The International Energy Agency and the United Nations Environment Programme’s 2018 Global Status Report on Climate Change reinforces that now, more than ever, it is imperative to design low-emission or zero-emission buildings. Buildings represent close to 40% of global energy-related carbon dioxide emissions, and as such, we have a responsibility to prioritize performance in the buildings we design.


More Than Half the World Lives in Towns and Cities

For the first time in history, the United Nations estimates that more than half of the global population live in towns and cities, and that by 2050, this proportion is expected to rise to two-thirds. As human population continues to increase and move into urban places, there is a need to re-envision how we design communities and buildings, and how we use energy and water resources. Cities are well poised to deliver more integrated and sustainable systems for energy, water and waste management putting less strain on the surrounding ecosystems. Over 80% of Canada’s population live in urban places.3


Climate Change is Clear

As leading climate researchers from NASA and the International Panel on Climate Change (IPCC) have reported, warming of the climate system is unequivocal. However, building awareness around the differences between Climate Change and Global Warming is needed as they are often used interchangeably but have different meanings. Similarly, the terms “weather” and “climate” are sometimes confused, though they refer to events with broadly different spatial and time scales.5 According to NASA:

  • WEATHER refers to atmospheric conditions that occur locally over short periods—from minutes to hours or days. For example, weather conditions include rain, snow, clouds, winds, floods or thunderstorms. Weather is local and short-term.6
  • CLIMATE is the weather conditions prevailing in an area in general or over a long period.7
  • CLIMATE CHANGE is a change in global or regional climate patterns. Climate change refers to a broad range of global phenomena created predominantly by burning fossil fuels, which add heat-trapping gases to Earth’s atmosphere. These phenomena include the increased temperature trends described by global warming, but also encompass changes such as sea level rise; ice mass loss in Greenland, Antarctica, the Arctic and mountain glaciers worldwide; shifts in flower/plant blooming; and extreme weather events.8
  • GLOBAL WARMING refers to the trend of increasing temperature across the entire Earth since the early 20th century, and most notably since the late 1970s, due to the increase in fossil fuel emissions since the Industrial Revolution. Worldwide since 1880, the average surface temperature has gone up by about 0.8°C (1.4 °F), relative to the mid-20th-century baseline (of 1951-1980).9


Humans Are the Cause

Human activities are estimated to have caused approximately 0.8 ˚C to 1.2 ˚C of global warming above pre-industrial levels to date. This anthropogenic climate change is caused by human activity, as opposed to changes in climate that may have resulted as part of Earth’s natural processes.

According to the IPCC 2018 Special Report on Climate Change10, global warming is likely to reach 1.5 ˚C between 2030 and 2052 if it continues to increase at the current rate. IPCC Climate models predict:

  • an increase in temperature in most land and ocean regions;
  • hot extremes in most inhabited regions;
  • heavy precipitation in several regions and probability of drought or insufficient precipitation in some regions;
  • sea level rise;
  • impact on biodiversity and ecosystems, including species loss and extinction;
  • risks to health, livelihoods, food security, water supply, human security and economic growth.

Limiting global warming will reduce these risks.


Change is Required

It is evident from the IPCC report that rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems are required to limit global warming to 1.5 °C. In order to do so, we will need global net Carbon Dioxide (CO2) emissions caused by human activity to decline by about 45% from 2010 levels by 2030, reaching ‘net zero’ around 2050, balancing emissions by removing CO2 from the atmosphere.12

As our climate changes, we can anticipate economic consequences, positive and negative, as well as changes in our ecosystems. For example, the London School of Economics estimates that climate change could eliminate US$2.5 trillion of the globe’s financial assets. A United Nations report also found that economic growth as measured by GDP would be 10%, or US$12 trillion, higher if the 1.5 °C threshold is achieved.13

Data from NASA satellites show that the land ice sheets in both Antarctica and Greenland have been losing mass since 2002 and that both ice sheets have seen an acceleration of ice mass loss since 2009. Antarctica has seen a loss of as much as 127 gigatonnes per year while Greenland has seen a loss of as much as 286 gigatonnes per year.14 This has resulted in 86 mm of sea level rise from melting ice sheets and glaciers as well as the expansion of sea water as it warms.15

Half of the world’s plant and animal species in the world’s most important natural places (Amazon and the Galapagos) are at risk of local extinction by the turn of the century due to climate change. Even if the Paris Climate agreement is met, these places could still lose 25 percent of their species.16


We Must Act Now

With this knowledge, we must act and transform how we build and operate our buildings. Buildings consume an extraordinary amount of energy through the extraction and manufacturing of materials, construction, and operations.

According to the United Nations Environment Programme and the International Energy Agency, buildings and construction account for more than 35% of global final energy use and nearly 40% of energy-related carbon dioxide (CO2) emissions.17

The design and construction industry have an important role to play in delivering low or zero emission buildings, improving occupant health and wellness, and the resilience of buildings and cities in the face of more extreme climactic conditions.



  2. “Water and Urbanization.” United Nations Water. (
  3. “Canada: Degree of urbanization from 2007 to 2017”. Statista. (
  4. “Scientific Consensus: Earth’s Climate is Warming.” NASA. (
  5. Ibid.
  6. Ibid.
  8. Ibid.
  9. Ibid.
  11. “Global Warming of 1.5 C.” Intergovernmental Panel on Climate Change (IPCC). (
  12. Ibid.
  13. “2017 Global Status Report.” UN Environment. (
  14. “Ice Sheets.” NASA. (
  15. “Sea Level.” NASA. (
  16. “Half of plant and animal species at risk from climate change in world’s most important natural places.” World Wildlife Fund. (
  17. “Global Status Report 2017.” UN Environment. (

Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming, edited by Paul Hawken, page xiv
“Fossil vs biogenic CO2 emissions.” IEA Bioenergy. (

“Carbon Dioxide Emissions Associated with Bioenergy and Other Biogenic Sources.” United States Environmental Protection Agency (EPA). (

“The Four Spheres of the Earth.” Thought Co. (

Regenerative Development to Reverse Climate Change.” The Commonwealth. (

“CO₂ and other Greenhouse Gas Emissions.” Our World in Data. (