The Heatwave We All Anticipated

February 14th, 2025

Why Indonesia Feels So Much Hotter Right Now? A Climate & Sustainability Perspective

It’s not just you. Currently, almost everywhere, days feel longer, nights bring less relief, and stepping outside often feels like stepping into an oven. From Jakarta to Makassar, many people are feeling the heat in a way that seems more intense than before. This isn’t just discomfort. It’s a signal that our climate is shifting faster than our adaptation.

What's driving the intense heat?

Natural climate patterns: El Niño and the Indian Ocean Dipole (IOD) — These natural climate patterns influence Indonesia’s weather. During El Niño years, rainfall tends to decrease in many parts of Indonesia; when combined with a positive IOD, the result is hotter, drier conditions and more intense dry seasons.
A hotter baseline: Human-driven global warming — We’re not starting from the same “normal” as decades ago. Rising greenhouse gas concentrations have increased average global and regional temperatures; that higher baseline makes any heat event, whether driven by El Niño or not, more intense and damaging than it would have been 30 years ago.
Deforestation and land-use change — Removing trees (for agriculture, plantations, or urban development) reduces natural cooling by evapotranspiration, lowers shading, and changes surface albedo. Lands that were once forested now heat up faster by day, and remain warmer by night because of reduced moisture and vegetation.
Urban Heat Island (UHI) effect — Cities in Indonesia are growing fast. Asphalt, concrete buildings, reduced green space, and dense construction trap heat, especially in the evenings. That means urban residents may suffer higher nighttime temperatures than rural or greener areas.
Changing Rainfall & Humidity Patterns — It’s not only temperature that matters. Changes in humidity, cloud cover, and seasonal rainfall can affect how the heat feels. Lower humidity during dry spells can reduce evaporative cooling (e.g., sweat evaporation), making high temperatures more stressful for people and crops.

How does it matter for our long-term daily life?

Extreme heat is not only uncomfortable, it creates cascading impacts across health, energy, food systems, and equity.

Public health: Heat stress increases the risk of dehydration, heat exhaustion, and heatstroke, especially for outdoor workers (farmers, construction crews, street vendors), older adults, and children. Local health systems are often unprepared for spikes in heat-related illness.
Energy and emissions: Higher temperatures drive stronger demand for cooling. If that extra electricity comes from fossil fuels, emissions increase, reinforcing the cycle that created the higher baseline in the first place. Grid strain during peak hours can also lead to outages if systems aren’t upgraded.
Agriculture and food security: Heat stress and longer dry spells can reduce crop yields and stress irrigation systems. Staple crops are vulnerable during critical growth phases, and farmers face increased costs and uncertainty.
Urban equity and planning: Heat exposure is often unequal. Lower-income neighborhoods frequently have less tree cover, less access to shaded public space, and buildings that retain heat, increasing vulnerability in communities least able to pay for adaptation measures.

It’s important to understand both the triggers and the context. El Niño and IOD are natural; but the climate context in which they operate is now warmer because of human emissions. That interaction turns what might have been a manageable warm spell into a health and infrastructure challenge. The IPCC and national assessments emphasize this interaction: human-caused warming increases the likelihood and intensity of extreme heat events and makes adaptation an urgent priority.

The blistering heat we feel today is a visible, everyday sign of a changing climate and of choices we have yet to fully make. While air conditioners offer immediate relief, long-term solutions require greener cities, cleaner power, smarter land management, and policies that protect those most at risk. The heat is real — and so is our capacity to respond, if we act now with both fairness and ambition.