Net-Zero Requires Improved Collaboration between Researchers and Policymakers

Global warming threatens the stability of the Earth system and, thus, the future of our society. In UNEP’s explainer of the global climate emergency (UNEP 2022), it notes that the world is not tracking well to meet the primary aim of the 2015 COP21 Paris Agreement, which is to keep “the increase in the global average temperature to well below 2°C above pre-industrial levels” and pursue efforts “to limit the temperature increase to 1.5°C above pre-industrial levels”. Although individual countries declared their Nationally Determined Contribution (NDCs) via legally binding carbon reduction pledges, they have not been meeting their pledges. Thus, the GHG emissions reduction gap is growing, and the time needed to achieve the target is narrowing.

The global average temperature in 2023 was 1.2 °C above the pre-industrial period (National Centres for Environmental Information 2023). Vulnerable communities and people groups have been, and are being, disproportionately impacted by climate related extreme events. Meanwhile, economies that historically and currently contribute the most to GHG emissions have not taken a proportionate emissions reduction target. In other words, there is a massive socio-economic equity gap.

At COP26 Glasgow, in addition to updated NDC pledges, the Breakthrough Agenda was launched to help the world close the widely recognised “collaboration gap” in key sectors and accelerate international action on climate change to meet the Paris Agreement’s global decarbonisation objective (Breakthrough Agenda 2021). Since then, an internationally-recognised, annual, COP-centred, collaborative process – backed by 59 countries – has focused on seven key sectors: power, road transport, steel, hydrogen, agriculture, buildings, and cement and concrete, covering over 60% of global emissions.

The Earth Commission has recently quantified the practical challenge that all sectors and actors need to aim for to keep the planet within a safe and just space based on Earth system boundaries (ESBs) (Gupta et al. 2024). This space or corridor is one in which pathways of future human development are both safe and just over time. In overcoming the key gaps to secure this space for humanity, their core nature, interdependencies and scope should be understood and addressed in the context of a jurisdiction or a country’s policy landscape (left side of Figure 1). The important role of science and the research community in breaking through these critical gaps is discussed herein.

Minding the built environment

The built environment is an important focus of action because the sector (including the related upstream and downstream processes) accounts for around 40% of energy and process related GHG emissions. However, the use of construction products is growing faster than the global population (OECD 2019), leading to the increased GHG emissions (Zhong et al. 2021). Similarly, operational emissions from energy use are rising by about 1% annually (IEA, IRENA & UN Climate Change High-Level Champions 2023). The embodied emissions of construction products and processes are increasing in both absolute and relative terms for individual buildings (Röck et al. 2020). The opportunities for operational emissions reduction of the building stock are significant, but the retrofit required to reduce the overall carbon footprint needs consideration of financial and carbon payback periods (Seo et al. 2018) as well as organisational and social implications.

Three of the seven key sectors in the Breakthrough Agenda – namely, buildings, steel, and cement and concrete – are core to the built environment and two (power and road transport) are closely related. The Buildings Breakthrough report was the first follow-up report that set out the sector’s priority agenda and actions (IEA et al. 2023). Significant emissions reduction in the three sectors’ value chain and their respective resource and mass flows have wider economy-wide and global impacts.

However, the projected global construction needs are significant. UN-Habitat estimates that by 2030, 3 billion people will need access to safe and sustainable housing (UN-Habitat 2023). Additionally, average per capita floor areas are expanding, and household sizes are shrinking, especially in countries experiencing strong population growth (UNDESA 2019).

Humanity faces a serious target conflict of construction to meet basic human needs and support socio-economic development while staying within a rapidly shrinking global GHG emission budget. Nevertheless, it is imperative that both objectives are addressed.

Minding the science

With massive barriers and shorter time frames, more than ever, fresh thinking is needed to find the most cost-effective paths that address the identified priority gaps. Determining ambitious NDC pledges need to be shown to be practically effective; drawing GHG emissions reduction lines are relatively easy but implementing the interventions and demonstrating their effectiveness are not. Despite the significant efforts and achievements to date of the Intergovernmental Panel on Climate Change (IPCC) to advance scientific knowledge about climate change caused by human activities since 1988, there appears to be a lack of adequate and effective policy action to match these acute challenges. But one of their less heralded achievements is the re-positioning of the critical importance of science to inform policy, investment and practice (via their awaited regular IPCC panel reports). This has been a long and slow process, but many in business, the media and the public can now be heard asking, “has that been peer-reviewed”? Unfortunately, this has also coincided with the spread of misinformation and disinformation by various vested interests. Not to be discouraged or defeated, researchers continue to call for a global-level scientific advisory that could support the UN and other inter-governmental stakeholders (Espey et al. 2024).

Thus, we advocate herein a fanning out of efforts to organise scientists and researchers in different and targeted areas of action in the economy to engage and support frontline decision makers.

Breaking a path: science towards a net-zero buildings and real estate sector

In the building, construction and real estate value chain, every stakeholder has a role to play (Hsu et al. 2022; IEA EBC Annex 72 2021). Policy instruments and other intervention schemes can be sharpened and combined (ürge-Vorsatz et al. 2007; Foliente & Seo 2012). Research support and evidence, including multi-scale scenarios modelling of their effectiveness sector-wide have advanced through the years.

But different socio-economic, regulatory, legal, and institutional structures need to be considered in developing country-relevant, bespoke solution sets (Bryson 2024).

With the development over the last 30 years of detailed understanding of GHG emissions from the built environment, our improved knowledge and data now need to be to be translated into more effective policy and practice, on one hand, while we also pursue more transformative, priority-gap-focused research via interdisciplinary and transdisciplinary research, development and delivery (RD&D).

Given the scope, complexity and urgency of the challenge, we need an approach in which those in different disciplines all contribute towards net-zero buildings. Climate science, environmental and earth sciences, life sciences, architecture, economics, law, social sciences, and other fields must collaborate to ensure solutions that minimise or effectively manage uncertainties and risks and avoid burden-shifting or unintended consequences. Table 1 provides examples of many relevant disciplines.

For example, finding solutions that balance climate protection, resource use, and land conservation without shifting burdens will require policies informed by diverse research perspectives and approaches. Similarly, incorporating externalities into market prices and managing them in public procurement processes require collaboration across disciplines and with other stakeholders in the construction value chain. Societal acceptance of rapid decarbonization and the necessary behavioural changes cannot be addressed solely from a climate protection perspective or by only highlighting the negative consequences. We also need to be talking about the societal and personal benefits of a healthy planet.

Breaking a path: an all-actors approach in an enabling policy environment  

Different stakeholder perspectives and types of action (regulation, voluntary action, business initiatives, community initiatives, professional initiatives) are essential to address the complex nature and consequences of the conflict between relatively short- to medium-term socio-economic development needs and the need for dramatic and sustained GHG emission reductions. The political, legal-regulatory and cultural dimensions of a local community or jurisdiction need to be central considerations to determine priority areas of actions, support a broad, systemic and sustained change, and avoid or mitigate unintended consequences.

Governments and international interjurisdictional bodies need to adopt cross-cutting, science-based approaches that are adapted to local needs and contexts (Espey et al., 2024). This will complement and provide an enabling environment for cities and businesses to more effectively contribute to our common goal (Gupta et al. 2024).

In setting regulatory requirements for new buildings, we need to pave the way for a whole-life GHG emissions target setting and reporting for buildings and real estate in relation to a country´s climate policy and NDCs. However, only the Netherlands, France, and Denmark currently have set GHG emission limits for new buildings. Sweden and Norway require the declaration of building emissions, and Germany has specific funding programs. Comparative reviews of different regulatory approaches are an emerging area of study (Kuittinen & Häkkinen 2020; Steinmann et al. 2022).

Although the European Union plans to limit the whole-life GHG emissions for individual new buildings by 2030, this alone will not solve the problem. While the EU is the fourth-largest global emitter with significant historical responsibility, its share is decreasing. Most 21st century construction will take place in developing countries with diverse regulatory, economic and cultural contexts.

Addressing in a more holistic way the GHG emissions reduction challenge of the whole building, property and real estate sector would require innovation, courage and a new ethic. This should be supported by new capabilities such as, or including, a comprehensive scenarios-modelling and digital platform to plan, explore, assess, monitor and manage net-zero decarbonisation pathways across the built asset’s life cycle considering the dynamic nature and the uncertainties of the key drivers that affect outcomes. The scope of impacts assessment needs to scale from individual buildings to the whole sector, and from a local site to neighbourhoods, cities and a whole nation. 

Strong and effective collaboration and their positive impacts should be accompanied by compelling social narratives.

Call to action

With narrowing time and opportunity to act, we call on responsible researchers from all disciplines and stakeholders to engage in broad and deep collaborations in support of globally ambitious but locally targeted policy and practice in the sector to keep our planet within the defined safe and just limits of temperature increase.

As the original 1992 "World Scientists' Warning to Humanity" (Union of Concerned Scientists, 1992) states:

“A new ethic is required—a new attitude towards discharging our responsibility for caring for ourselves and for the earth…  This ethic must motivate a great movement, convincing reluctant leaders and reluctant governments and reluctant peoples themselves to effect the needed changes…

•    We require the help of the world community of scientists—natural, social, economic, and political.
•    We require the help of the world's business and industrial leaders.
•    We require the help of the world's religious leaders.
•    We require the help of the world's peoples.

We call on all to join us in this task.”

In this same spirit, we now invite you to join us and sign-up also to the Researchers’ Call to Action for Breakthrough Decarbonisation Policies in the Building Sector.

References

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