Historical Study of Climate Change

1.1  Climate Change in Current World

 

Carbon dioxide concentration has reached the highest level in 2 million years (NOAA), 2022; R. Lindsey, 2024), with Taiwan ranking 19th in the world for per capita carbon emissions (H. Ritchie and M. Roser, 2024; H. Ritchie, 2024), and the Taichung Power Plant’s global pollution impact (Monitor, 2023; J.-C. Chuang, 2023; Y.-C. Huang et al., 2020). Glaciers are retreating at the fastest rate in 2,000 years (IPCC, 2021), and Greenland’s ice melt alone could raise global sea levels by 7.4 meters ((NSIDC), 2023). By 2050, global warming is expected to exceed 1.5°C (WMO, 2025), putting 30% of species at risk of extinction (IPCC, 2022; IPCC, 2007). Extreme heat events are intensifying (IPCC, 2021), sea ice extent has dropped to the lowest in 1,000 years (IPCC, 2021), and the distribution of droughts and heavy rainfall is becoming more polarized (IPCC, 2021). Marine heatwaves and intense rainfall are increasing in frequency and strength (IPCC, 2021; IPCC, 2023), while ice sheet collapse and changes in ocean circulation accelerate (IPCC, 2021; P. Ditlevsen and S. Ditlevsen, 2023; IPCC, 2021). Sea level rise is now at its fastest pace in 3,000 years (IPCC, 2021), with island nations such as Tuvalu already disappearing (NASA, 2023; Trade, 2023; Australia, 2023; Reuters, 2025). Together, these facts highlight the urgent and undeniable reality of climate change, underscoring the need for immediate global action.

 

 1.2   Global Temperature Goal

 

Global mean surface temperature has risen steadily since the late 19th century, accelerating after the Second Industrial Revolution and the large-scale use of electricity. Observations show an increase of over 1.0°C above pre-industrial levels, with the period 2006–2015 significantly warmer than 1986–2005. Current warming exceeds the natural Holocene range, and IPCC projections indicate further increases driven by human activities, underscoring the urgent need for global climate action.

 

To limit the global average temperature rise within 1.5°C, the Intergovernmental Panel on Climate Change (IPCC) uses Representative Concentration Pathways (RCPs) to model possible greenhouse gas emission trajectories. These scenarios illustrate how different levels of human-induced emissions influence long-term warming. Achieving the 1.5°C target requires ambitious reductions: global emissions must decline by 40–70% compared to 2010 levels by 2050 and reach net zero or even negative levels by 2100. Among the RCPs, only RCP2.6 aligns with the 1.5°C pathway, demanding rapid decarbonization and large-scale deployment of negative emission technologies, while higher emission scenarios such as RCP4.5, RCP6, and RCP8.5 would result in significantly greater warming between 1.7°C and more than 5°C. This underscores the urgency of immediate and sustained global action to achieve deep emission cuts and transition toward a net-zero future.

1.3   7 Main Green House GAS

The seven greenhouse gases with the greatest impact on global warming are carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF₆), and nitrogen trifluoride (NF₃) (IPCC, 2006; IPCC, 2019; EPA, 2022). CO₂ primarily comes from burning fossil fuels, wood, and waste, as well as deforestation (EPA, 2022). CH₄ is released during coal, oil, and natural gas production and transport, biomass burning, livestock digestion, rice cultivation, and landfill decomposition (EPA, 2022). N₂O emissions are linked to fossil fuel combustion and fertilizer use (IPCC, 2019; EPA, 2022). HFCs and PFCs are generated in semiconductor and electronics manufacturing, with HFCs also serving as major refrigerants (IPCC, 2006; EPA, 2022). SF₆ is used in the semiconductor and power industries as an insulating gas and in fire suppression (IPCC, 2006; EPA, 2022), while NF₃ is used in producing LCDs, solar panels, and small electronic circuits (IPCC, 2006; EPA, 2022). To compare their climate impact, all are measured in carbon dioxide equivalent (CO₂e) based on their global warming potential (IPCC, 2006; IPCC, 2019).

 1.4  Global Climate Negotiations

Global climate negotiations have progressed from early environmental awareness in the 1972 Stockholm Declaration and the creation of UNEP, to the establishment of the IPCC in 1988 and the adoption of the UNFCCC in 1992. The Kyoto Protocol in 1997 introduced binding emission targets and market mechanisms, while the 2015 Paris Agreement marked a turning point with universal commitments to limit warming to well below 2°C and pursue 1.5°C through nationally determined contributions. More recent developments, including the EU Green Deal, taxonomy and disclosure regulations, COP26’s net-zero pledge by 2050, and the introduction of the Carbon Border Adjustment Mechanism, highlight a shift toward comprehensive climate governance that integrates emissions reduction, sustainable finance, and global accountability.

 

Global climate negotiations have progressed from early environmental awareness in the 1972 Stockholm Declaration (Nations, 1972) and the creation of UNEP (IPCC, 1988), to the establishment of the IPCC in 1988 (Nations, 1992) and the adoption of the UNFCCC in 1992 (Nations, 1997). The Kyoto Protocol in 1997 introduced binding emission targets and market mechanisms (Unknown, n.d.), while the 2015 Paris Agreement marked a turning point with universal commitments to limit warming to well below 2°C and pursue 1.5°C through nationally determined contributions (Union, 2019). More recent developments, including the EU Green Deal (Union, 2020), taxonomy and disclosure regulations (Nations, 2021), COP26’s net-zero pledge by 2050 (Union, 2022), and the introduction of the Carbon Border Adjustment Mechanism (Union, 2023), highlight a shift toward comprehensive climate governance that integrates emissions reduction, sustainable finance, and global accountability.

Global Climate Change International Negotiation Timeline

 

 1.5  Global Green House Gas Emission’s Status

Global greenhouse gas emissions reached a record high in 2023, totaling 53 gigatons of CO₂ equivalent, an increase of nearly one gigaton compared to the previous year (Unknown, n.d.; UNEP, 2024). Fossil fuel–related CO₂ remains the dominant driver, accounting for almost three-quarters of total emissions (EPA, 2024).

When we look at where these emissions come from, the picture is highly concentrated. Just a handful of major economies — including China, the United States, the European Union, India, Russia, and Brazil — are responsible for more than 62 percent of global emissions (UNEP, 2024). China alone contributed over 13 gigatons, while India emitted nearly 3 gigatons (UNEP, 2024; JRC, 2024).

Growth trends are also concerning. China, India, Russia, and Brazil all reported increases, with India showing the strongest growth at around six percent (UNEP, 2024). Looking ahead, coal combustion in 2024 is expected to rise by nearly one percent, largely driven by continued demand in Asia ((IEA), 2024).

It’s important to highlight methane as well. In 2023, fossil methane emissions reached about 120 million tons. The United States leads methane emissions from oil and gas operations, while China is the largest emitter from coal mining ((IEA), 2024).

The challenge is clear. Under current policies, we are on track for around 3.1 degrees of warming (Nations, 2023). Even if all national commitments, or NDCs, are fully implemented, global warming would only be reduced to about 1.9 degrees, still far above the Paris Agreement’s 1.5-degree target (Nations, 2023). This underscores the urgent need for deeper and faster emission cuts across all sectors and regions.

 

 

1.6   Taiwan’s Climate Policy

1.6.1          Taiwan's Climate Legislation and Net-Zero Policy

According to the 2021 National Greenhouse Gas Emissions Inventory Report, Taiwan’s total greenhouse gas (GHG) emissions rose from 137.76 million metric tons of CO₂ equivalent (excluding removals) in 1990 to 287.06 million metric tons of CO₂ equivalent in 2019 (excluding removals) (EPA Taiwan, 1990). After accounting for a carbon sink of 21.44 million metric tons of CO₂ equivalent, the net emissions amounted to 265.62 million metric tons of CO₂ equivalent—a 3.6% decrease compared to 2018 and a 1.1% decrease compared to 2005 (EPA Taiwan, 1990). The data are illustrated in the figure below (EPA Taiwan, 1990).

 

1.6.2          2050 Taiwan to NetZero

 

Taiwan has set a clear pathway toward achieving net zero greenhouse gas emissions by 2050. This commitment is driven by three key forces: the global challenge of the climate emergency, the international trend toward net-zero carbon emissions, and the rise of green supply chains alongside carbon border taxation. To establish a legal foundation, Taiwan amended the Greenhouse Gas Reduction and Management Act on January 10, 2023, renaming it the Climate Change Response Act. The revised law sets a long-term national goal of reaching net zero emissions by 2050. Implementation will require joint efforts from all levels of government, citizens, businesses, and organizations, turning the climate crisis into an opportunity to unlock new business potential.

  

1.6.3          Accelerating Decarbonization and Enhancing Industrial Competitiveness

 

 

This infographic outlines six key strategies for accelerating carbon reduction and enhancing industrial competitiveness.

l   First, Inventory and Verification (Articles 21 & 22) introduces tiered management and strengthens verification capacity .

l   Second, Efficiency Standards (Article 23) set requirements for product production processes, manufacturing or importing vehicles, and new buildings .

l   Third, Stable Implementation of Carbon Trading (Article 25) encourages voluntary reductions and establishes demand-driven mechanisms for quota trading , (UNEP, 2024).

l   Fourth, Carbon Fee Collection (Article 28) uses economic tools to promote reduction and incentivizes emission cuts through fee collection and payment mechanisms.

l   Fifth, Responding to International Carbon Border Adjustment (Article 31) ensures compliance with global trade trends by requiring importers to declare carbon content and adjusting reduction quotas accordingly (EPA, 2024).

l   Finally, Carbon Capture, Utilization, and Storage (Article 39) promotes the development of negative-carbon technologies and incorporates environmental impact into management (JRC, 2024).

Together, these measures aim to strengthen Taiwan’s competitiveness in the global low-carbon economy.

 

• Entity Accounting (ISO 14064-1:2018)
  Aggregates organizational emissions and compares them to a base year in order to track changes over time (ISO, 2018).
• Project Accounting (ISO 14064-2:2019)
  Estimates avoided or reduced emissions from specific projects by comparing “business-as-usual” scenarios with actual project outcomes (ISO, 2019).
• Product Accounting (ISO 14040 or ISO 14067)
  Uses Life Cycle Assessment (LCA) methodologies to evaluate the total impact of a product or service from raw material extraction through manufacturing, distribution, consumption, and disposal (ISO, 2018).

Carbon Accounting (also known as carbon inventory) refers to the systematic process of collecting, calculating, and analyzing greenhouse gas (GHG) emissions data. It follows internationally and domestically recognized standards such as the GHG Protocol ((WBCSD), 2004), ISO 14064-1 (ISO, 2018), and the Environmental Protection Administration (EPA) Guidelines for GHG Emissions Inventory ((EPA), 2020), to ensure the accuracy and consistency of both direct and indirect emissions measurement. Through carbon accounting, organizations can identify their major emission sources and hotspots. The results may be presented as a basic GHG emissions inventory or as a comprehensive carbon accounting report that can be disclosed to stakeholders to demonstrate transparency, accountability, and commitment to climate action.

 

2.5  Greenhouse Gas (GHG) Emission Categories (Scope 1, Scope 2, Scope 3) (Part of ISO14064-1)

 

Greenhouse gas (GHG) emissions are categorized into three scopes.

• Scope 1: Direct Emissions
  These are emissions from sources owned or controlled by the organization, such as boilers, company vehicles, industrial processes, fire extinguishers, refrigeration systems, and land use ((WBCSD), 2004), (ISO, 2018).
• Scope 2: Energy Indirect Emissions
  These result from the consumption of purchased electricity or energy (including renewable energy). Though the emissions occur at the power generation source, they are attributed to the organization that uses the electricity ((WBCSD), 2004).
• Scope 3: Other Indirect Emissions
  These include all other indirect emissions that occur in the value chain, such as upstream transportation, raw material purchases, capital goods, employee commuting, business travel, downstream logistics, outsourced services, product use, investments, and customer visits ((WBCSD), 2004), (ISO, 2018).

This classification framework provides a comprehensive view of an organization’s total carbon footprint and is essential for carbon accounting and sustainability reporting ((WBCSD), 2004), (ISO, 2018).

2.6   Example for Scope 2

The calculation of greenhouse gas (GHG) emissions based on the emission factor method provides a standardized approach for organizations to quantify their carbon footprint. The general formula is expressed as:

where (E) represents the emissions from a specific source (measured in kg CO₂e), (A) denotes the activity data (e.g., electricity consumption, fuel use, production output), and (EF) is the emission factor corresponding to the activity, typically obtained from national inventories or international databases.

For example, the emissions from purchased electricity can be calculated as:

 If an organization consumes 1000 kWh of purchased electricity and the official emission factor for that year is 0.474 kgCO₂e/kWh, the resulting emissions are:

This approach is widely adopted in corporate carbon accounting and national greenhouse gas inventories as it ensures consistency, transparency, and comparability across reporting entities. It is also aligned with international standards such as the GHG Protocol and ISO 14064-1, which require organizations to apply activity data and appropriate emission factors to calculate both direct and indirect emissions ((WBCSD), 2004)–(FPT Information System, 2024).

2.7  Carbon Footprint (ISO14067)

A carbon footprint refers to the total greenhouse gas (GHG) emissions generated by a product or activity throughout its life cycle, including upstream and downstream processes, and their contribution to climate change. To ensure methodological rigor and data reliability, organizations apply internationally and domestically recognized standards such as PAS 2050, ISO 14067, and the EPA Guidelines for Product Carbon Footprint Management (FPT Information System, 2024)–(ISO, 2019).

This comprehensive life-cycle-based approach, usually expressed in CO₂ equivalent (kgCO₂e), enables organizations to identify environmental hotspots, quantify emission sources, and develop effective strategies for emission reduction across the full supply chain (ISO, 2019), (ISO, 2018).

 

Life Cycle Stages of Carbon Footprint

 

The life cycle carbon footprint of a product is typically assessed across five sequential stages. Step 1 (Raw Material Acquisition) involves resource extraction, deforestation, and related upstream environmental burdens (FPT Information System, 2024). Step 2 (Manufacturing) encompasses energy consumption, direct GHG emissions, pollution, and resource depletion within production processes (ISO, 2018). Step 3 (Distribution) covers emissions associated with logistics, packaging, and energy use across supply chains (ISO, 2019). Step 4 (Usage) accounts for operational energy consumption, consumer behavior, and social or environmental burdens (ISO, 2019). Finally, Step 5 (Disposal) addresses end-of-life pathways such as recycling, incineration, or landfill, where methane and CO₂ emissions represent significant contributors to the overall footprint (ISO, 2018).

By integrating these stages, the carbon footprint methodology offers a holistic view of climate impacts and provides a foundation for corporate sustainability reporting, eco-labeling, and low-carbon product design (FPT Information System, 2024)–(ISO, 2018).