Natural hazards (tectonic, weather, climate change)

The contrast between two well-known earthquakes strongly supports the statement. On 27 February 2010 an earthquake of magnitude 8.8 struck off the coast of central Chile, one of the most powerful ever recorded, yet around 525 people died¹. On 25 April 2015 a magnitude 7.8 earthquake struck Nepal, releasing roughly 30 times less energy², but nearly 9,000 people were killed. The weaker earthquake killed about 17 times as many people, which suggests that the country's level of development mattered more than the strength of the shaking.

Development explains much of this difference because it controls how vulnerable people are. Chile is a relatively wealthy country with a long history of earthquakes, including the 1960 Valdivia earthquake, the strongest ever recorded, so it has strict building codes that are enforced³. Most modern buildings flexed rather than collapsed, so primary effects such as deaths from collapsing buildings were limited. Chile's well-funded emergency services also responded quickly. In contrast, Nepal was a low-income country where many homes were built from unreinforced brick and stone, and building rules were poorly enforced, so hundreds of thousands of houses were destroyed and people were crushed inside them. Nepal's mountainous terrain and limited road network meant that landslides cut off villages, so rescue teams and aid took days to arrive⁴ and injured people went without treatment, increasing secondary effects.

However, development does not reduce every effect⁵. Chile's damage was estimated at up to around 30 billion US dollars, far more than Nepal's (around 7 billion US dollars) in absolute terms, because a richer country has more valuable buildings, roads and ports to lose. The real difference is in the ability to cope: Chile could afford to rebuild quickly, whereas Nepal's losses were equivalent to around a third of its annual GDP, so recovery was slow and depended heavily on international aid.

Other factors also shaped the effects, so the strength of the earthquake and its physical context still matter. Nepal's earthquake was shallow and its epicentre was on land, about 80 km from the capital Kathmandu, whereas Chile's epicentre was offshore. Secondary hazards also depend on physical geography: Chile's coast was hit by a tsunami, while in Nepal the earthquake triggered landslides and an avalanche at Everest Base Camp. Timing played a part too⁶: Nepal's earthquake happened around midday on a Saturday, the weekly day off, so schools were empty, which probably prevented many child deaths.

Overall, I agree with the statement to a large extent⁷. Strength, depth and location decide the size of the hazard, but the level of development decides how many people are harmed by it. A magnitude 8.8 earthquake in Chile killed far fewer people than a 7.8 in Nepal, which shows that development is the more important factor for human effects, even though wealthier countries may suffer larger economic losses in absolute terms.

Mitigation means reducing the causes¹ of climate change by cutting greenhouse gas emissions or removing carbon dioxide from the atmosphere. One method is switching from fossil fuels to renewable energy such as wind and solar power. These produce electricity without burning carbon, so less carbon dioxide enters the atmosphere and the enhanced greenhouse effect is weakened². The UK closed its last coal-fired power station, Ratcliffe-on-Soar, in 2024. A second method is international agreements. In the 2015 Paris Agreement³, almost every country agreed to try to keep global warming well below 2°C, so countries set targets to cut emissions. Planting trees (afforestation) also helps, because trees absorb carbon dioxide during photosynthesis and store it as carbon.

Adaptation means changing how we live so that people are less affected by the impacts of climate change that cannot be avoided. As sea levels rise, coastal and estuary areas face more flooding, so flood defences are built or improved⁴. For example, the Thames Barrier protects central London from storm surges and is part of a long-term plan to keep London safe as sea levels rise this century. In farming, drought-resistant crop varieties and more efficient irrigation allow farmers to keep producing food as rainfall becomes less reliable, which protects food supply and incomes⁵.

Mitigation therefore tackles the long-term cause, while adaptation reduces the harm that climate change is already causing.