Climate change is one of the greatest challenges of the 21st century. It is no longer just a scientific issue but a growing part of daily life. What was once seen as a distant threat now appears through record breaking heatwaves, stronger typhoons, rising sea levels, and stressed ecosystems (Figure 1a). While climate models continue to advance, extreme events are happening faster than predictions. Tackling this crisis calls for cooperation across science, engineering, economics, and policy (Figure 1b).
Climate change refers to long term shifts in Earth's climate, including temperature, rainfall, and the frequency of extreme weather. Natural factors like volcanoes and solar cycles have always influenced the climate, but human activity has rapidly increased warming since the Industrial Revolution. Burning fossil fuels, clearing forests, and intensive farming have raised levels of greenhouse gases like carbon dioxide and methane, trapping more heat and pushing global temperatures upward.
One key impact is uneven heating of the planet. Oceans absorb over 90 percent of the extra heat (Figure 2), disrupting circulation systems like the Pacific Walker Circulation and the Indian Ocean Dipole. These changes affect rainfall, monsoons, and marine ecosystems. Warmer oceans and a wetter atmosphere are already causing stronger cyclones and more intense rain. This leads to a pattern often described as "wet becomes wetter, dry becomes drier."
The Arctic is warming at more than twice the global average, a trend called Arctic amplification (Figure 3). Melting sea ice and thawing frozen ground in northern regions affect not only local systems but also global weather. Shifts in the jet stream and slow moving high pressure systems can bring heatwaves and cold spells to midlatitude areas. At the same time, rising temperatures are disturbing ecosystems around the world. Insects may reproduce less, food chains may be disrupted, and important processes like nutrient cycling can slow down.
Climate change also increases inequality. Communities with fewer resources, such as small farmers, coastal villages, and low income workers, face greater risks. In Vietnam's Mekong Delta, sea level rise and saltwater intrusion are pushing people to switch from rice farming to shrimp aquaculture. While this shift may bring new income, it also brings risks like disease and financial instability.
This edition of NTU Highlights features how the College of Science is addressing climate change through five key articles:
1. The Ocean's Influence on Climate: A Silent Force Shaping Regional Weather Patterns
2. Typhoons and Climate Change
3. The Arctic Chain Reaction in a Changing Climate
4. Climate-Change-Induced Extreme Events and Their Social Impacts
5. Climate Change and Ecosystem Shifts: What Burying Beetles Can Teach Us
Figure 1 A dramatic contrast between two futures: (left) (a) impacts of climate change with drought, land degradation, and ecological stress and (right) (b) a vision of sustainability with urban resilience, renewable energy, and thriving ecosystems. Figure was created using ChatGPT based on input from Yen-Ting Hwang (2025).
Figure 2 Sea-surface temperature trends from 1979 to 2024 from NOAA ERSST (https://www.ncei.noaa.gov/products/extended-reconstructed-sst). Figure credit: Wen-Hsin Lo
Figure 3. Global temperature differences for 2000 to 2009, extracted from the NASA Earth Observatory.