Why Europe Is Burning While Malaysia Remains Warm: Seas, Sweat, Air-Conditioning, and the Lessons of the Highlands
By lim ju boo - Chinese name lin ru wu (林 如 武)
I saw over Singapore CNA television, BBC World news, and read several news reports elsewhere, currently Europe is experiencing an unprecedented, record-breaking heatwave, with the World Health Organization (WHO) linking it to more than 1,300 excess deaths. Spain peaked at an intense 44.7 degrees. In El Granado, Spain the country recorded over 1,000 heat-related deaths in June alone. France surged past 40 degrees C leading to mortuaries in Paris reaching capacity due to a sharp spike in heat-related fatalities. German broke its national all-time record, hitting 41.5 degrees C. In the UK in June 2026 was the warmest on record for England. While the UK was swept by record-breaking temperatures and warm nights last week with a record-high of 23.5 degrees C overnight minimum, the extreme heat have since moved into central and eastern Europe, bringing relief to the west.
As Europe experiences record-breaking heatwaves, with temperatures rising above 40°C in several countries and heat-related deaths mounting, many Malaysians may or may not naturally ask: why does Europe, known for its cool temperate climate, become so dangerously hot, while Malaysia near the Equator remains warm but comparatively stable?
The answer lies partly in geography, partly in physics, partly in human physiology, and increasingly in climate change.
Europe is a vast continental landmass. Malaysia, by contrast, is a maritime tropical country. Peninsular Malaysia lies between the South China Sea to the east and the Strait of Malacca to the west, while Sabah and Sarawak on Borneo also face the South China Sea. Indonesia, the Philippines, and much of Southeast Asia are likewise surrounded by seas and oceans. It is therefore more accurate to describe Malaysia as ocean-influenced or maritime, rather than “sea-locked,” because sea-locked normally means surrounded by land.
This difference is extremely important. Land heats up quickly under the Sun and cools quickly after sunset. Water behaves very differently. The sea warms slowly because water has a very high specific heat capacity: about 4.184 kilojoules are needed to raise the temperature of one kilogram of water by 1°C. Thus, the enormous surrounding seas act like a giant thermal cushion. They absorb large quantities of solar energy during the day and release that energy gradually later.
The sea therefore reduces the great temperature swings that occur over dry continental land. In Malaysia, daytime temperatures are usually warm, often around 30–33°C, but they rarely rise to the frightening extremes now seen in parts of Europe. At night, the sea remains relatively warm, so temperatures do not fall sharply either. This produces the familiar Malaysian pattern: warm days, warm nights, high humidity, clouds, rain, and relatively little seasonal variation.
Water also cools the environment through evaporation. To evaporate one kilogram of water requires approximately 2,260 kilojoules of energy—an enormous amount. This energy is taken from the sea surface and the surrounding air. It does not disappear; it is stored as latent heat in water vapour. When the vapour later condenses to form clouds and rain, the stored energy is released high in the atmosphere, helping to drive thunderstorms, winds, and weather systems.
The atmosphere must also lift immense quantities of moist air upward.
If one kilogram of water were lifted vertically by 4,000 metres, the gravitational potential energy (PE) required would be:
PE in Joules = mgh
where,
m = mass of the object (water vapour) in kilograms
g = acceleration due to gravity. On Earth, this is a constant approximately equal to 9.81 m/s ^2
h = vertical height (or distance) measured in meters
This stored energy can be converted into other forms, such as kinetic energy (motion) when the object is dropped, such as rains.
Thus the PE of 1 kg of water vapour to a height of 4,000 meters as rain cloud = 1 x 9.81 x 4,000 = 39,240 joules or 39.24 kJ.
This is much smaller than the 2,260 kilojoules needed to evaporate that kilogram of water, but it illustrates the immense energy involved when countless tonnes of moist air rise daily from tropical seas. In reality, air does not rise like water being lifted by a crane. It rises through convection, thunderstorms, and large-scale weather circulation. Nevertheless, the tropical atmosphere is continuously transporting astonishing amounts of heat and water upward.
Malaysia’s rain clouds may begin only a few hundred metres above the ground, but towering thunderclouds can rise to 10–15 kilometres or more. The tropical sea, the clouds, the rain, and the green vegetation together form a great natural cooling and recycling system.
Malaysia’s forests, jungles, crops, and vegetation also absorb solar energy. Plants use part of this energy for photosynthesis and growth. More importantly, they release water vapour through transpiration. This process is rather like evaporation from the sea and helps cool the local environment. Forests are therefore not merely green scenery; they are part of the climate-regulating machinery of the Earth.
Malaysia experiences a lot of rain.
Heavy rain in Malaysia generally yields 30,000 to 60,000 tons of water per square kilometer every hour. In cases of very heavy or extreme downpours, this volume can exceed 60,000 to 100,000+ tons per hour.
Let me use a standard 30 mm / hour downpour as an example:
First, rain intensity is measured in millimeters per hour. 1 mm of rain equals 1 liter of water over 1 square meter of land.
Therefore, 30 mm / hour equals 30 liters per square meter each hour.
Since 1 square kilometer is
1,000,000 square meters,
that yields 30,000,000 liters of
water per hour.
Since 1,000 litres of water weighs exactly 1 metric ton, this equals 30,000 tons of water per square kilometre. Consider, when rain falls it does not fall on just one square metre of land. Probably tens of hundreds of thousands square metres of land throughout Malaysia will be affected by rainfall since the total area of Peninsular Malaysia is approximately 132,090,000,000 square metres (132.09 billion square metres).
Thus the cooling influence of frequent tropical rain is not trivial. A heavy downpour of 30 mm an hour over one square kilometre means that about 30,000 tonnes of water fall from the sky in a single hour. At
60 mm an hour, the amount
becomes about 60,000 tonnes. In
exceptionally intense tropical storms,
the volume may exceed 100,000 tonnes of water per square kilometre in an hour.
The energy involved is immense. To raise one kilogram of water vapour to a cloud height of about 4,000 metres requires approximately 39,240 joules of gravitational potential energy. Thus, lifting 30,000 tonnes of water to that height represents about 1.18 x 10^12 joules of energy, while 60,000 tonnes represents about 2.35 x 10^12 joules. That's a enormous amount of heat energy lost. This cools the land.
Yet the far greater energy requirement comes earlier, when sunlight evaporates water from the sea, rivers, wet ground, vegetation, and other surfaces. To evaporate one kilogram of water (latent heat of evaporation) requires roughly 2.26 million joules of latent heat—about 58 times more energy than is needed to lift that same kilogram of water to a height of 4,000 metres. This energy is not destroyed. It is stored temporarily in water vapour and later released high in the atmosphere when vapour condenses to form clouds and rain.
Malaysia’s frequent rainfall therefore acts as part of a vast natural heat-transport system. Clouds reduce the amount of direct sunlight reaching the ground. Rain wets the soil and vegetation, while evaporation from these wet surfaces consumes large amounts of heat that would otherwise raise the temperature of the land and air. Much solar energy is thus diverted into the evaporation–condensation–rainfall cycle instead of directly heating the surface.
In drought-stricken parts of Europe, the opposite may occur. When soils become dry and vegetation loses moisture, there is far less water available for evaporation. More of the Sun’s energy then goes directly into heating the land and the lower atmosphere. This is one important reason why prolonged dry spells can intensify and prolong heat waves over large continental regions.
Europe during a heatwave experiences almost the opposite situation. A persistent high-pressure system, sometimes described as a “heat dome,” settles over the continent. Air sinks, compresses, and warms. Clouds disappear. The Sun beats down day after day. Dry soil cannot evaporate much water, so solar energy goes directly into heating the ground and the air. Hot air may also be drawn northward from North Africa or the Mediterranean region.
This is made worse by climate change. Carbon dioxide, methane, and other greenhouse gases raise the Earth’s baseline temperature. They do not create every heatwave, but they make heatwaves more likely, hotter, longer, and more dangerous. A heatwave is like a flood: the weather event may be the storm, but climate change has already raised the water level in the river.
Europe is also warming faster than the global average. Its cities are especially vulnerable because concrete, asphalt, brick, and roofs absorb heat during the day and release it slowly at night. This is called the urban heat-island effect. Warm nights are particularly dangerous because the human body has little opportunity to recover from daytime heat.
The normal core temperature of the human body is around 37°C, although it varies slightly from person to person and through the day. If the surrounding air is around 30°C, the body can still lose heat to the environment, but not very efficiently. The body loses heat by radiation, convection, conduction, and evaporation.
In hot Malaysia, evaporation of sweat becomes increasingly important. Much sweating may be so mild that it is hardly noticed. The thin film of moisture on the skin evaporates quietly into the air and carries heat away.
This is what we calls “invisible sweat,” and it is a useful everyday description. After a warm bath, however, there is more water on the skin. As it evaporates, it produces a noticeable cooling sensation for several minutes.
Even before or after bathing much sweating may be so mild that it is hardly noticed. The thin film of moisture on the skin evaporates quietly into the air and carries heat away. We may think of this as “invisible sweat,” an everyday description of the body’s quiet cooling process.
Normally I would bathe twice a day in Malaysia but only once daily when I was a student in England and at the Massachusetts Institute of Technology (MIT) where the average temperature was 8° C to 10 degrees C.
Here in warmer Malaysia I bathe twice a day - in the morning or afternoon, and at night before bed to cool off slightly, but more importantly to remove sweat and body oil especially on my face and neck before going to bed. The tap water temperature is always at 28.5 ° C day or night taken from several randomized readings. The water pipes run underground where the temperature is constant day or night. It only emerges for a very short distance in the house where the water metre is, and if the pipe is on the rooftop exposed to the sun in the day, the water can be very hot for a few minutes if the tap is not used for an hour or longer. After a few minutes of running the tap, the temperature drops to a cool 28.5 ° C. With a difference of only 1.5 o C between room and tap water temperatures, it is very cool and comfortable to bathe directly from the tap without even using hot water. Even if we use hot water to bathe, the temperature of the hot and cold water is only between 32.5 to 35 degrees C. depending how we control the flow volume of hot water tap - its mixture ratio and flow rate
A fan does not usually lower the actual temperature of the room, nor does it normally change the reading of an ordinary dry-bulb thermometer. But it helps the human body because moving air carries away the warm layer of air next to the skin and speeds evaporation of sweat. In humid weather, however, sweat evaporates poorly. This is why a Malaysian day of 32°C with high humidity may feel far more uncomfortable than a dry 32°C day elsewhere. In my house indoors the dry bulb thermometer always stays at 30 ° C day and night. If it fluctuates it is always just one degree higher or lower. A wet-bulb thermometer works on this principle. It has a wet wick around its bulb. As water evaporates from the wick, the thermometer cools. The difference between dry-bulb and wet-bulb temperatures helps indicate the humidity of the air. When humidity is high, little evaporation occurs, and the wet-bulb temperature remains high. This is dangerous because human sweating then becomes less effective.
Malaysia’s temperature remains relatively stable throughout the year because it lies close to the Equator. There are monsoon seasons, rainy periods, dry spells, and local variations, but there is no true winter. Higher places, however, are cooler because air temperature generally falls with altitude. Cameron Highlands and Fraser’s Hill are examples of this.
Cameron Highlands was discovered in 1885 by William Cameron, a British government surveyor, and was later developed by the colonial administration as a hill station. Fraser’s Hill also became a hill retreat in the early twentieth century. These places were attractive to British colonial officers, planters, administrators, and families because their higher elevation offered cool air, mist, forests, and relief from the heat and humidity of the lowlands. Fraser’s Hill, at roughly 1,500 metres above sea level, still retains Tudor-style buildings and an English village atmosphere. Cameron Highlands likewise developed with bungalows, gardens, tea plantations, and architecture reminiscent of Britain.
The British did not invent air-conditioning in Malaya. Modern mechanical air-conditioning was developed in the United States in the early twentieth century, most famously associated with Willis Carrier. But British colonial administration did help introduce and normalize electric fans, modern ventilation, and later air-conditioning in urban Malaya—in offices, clubs, hotels, hospitals, government buildings, and affluent homes.
The British were accustomed to a much cooler climate. In England, homes, hostels, offices, and public buildings needed central heating to protect people from winter cold. When British officials came to Malaya, they faced the reverse problem: heat, humidity, insects, heavy rain, and tropical nights. They sought relief through fans, hill stations, shaded verandahs, high ceilings, ventilation, and eventually air-conditioning.
Today, Malaysians sometimes experience an odd contrast. Outside, the weather may be 31°C or 33°C. Inside an office, clinic, hospital, shopping mall, or meeting room, the air-conditioning may be set at 18°C or 20°C. A person may then have to dress for two climates on the same day: tropical heat outdoors and near-winter cold indoors.
Many people, especially those accustomed to Malaysia’s warm climate, feel uncomfortable after sitting for hours in strongly air-conditioned rooms. My observation that my back feels especially cold in such places is understandable. The back and shoulders are often exposed directly to air-conditioning vents. When one sits still, the body produces less muscular heat, while moving cold air increases convective heat loss from the skin. The large surface area of the back, shoulders, and upper arms may therefore feel chilled quickly.
The spinal cord itself is not being directly “cooled” by the air-conditioner, because it is protected deep inside the vertebral column. But the skin, muscles, and superficial nerves of the back can feel cold, stiff, or uncomfortable. Cold moving air may also cause muscles around the neck, shoulders, and back to tense. This can produce aching, tightness, or a sensation of discomfort. A light sweater, shawl, or jacket over the shoulders and back reduces heat loss from the skin and muscles, which is why many office workers instinctively use one.
Nevertheless, tropical adaptation should not be misunderstood. Malaysians may be more accustomed to warmth, lighter clothing, open windows, fans, and natural ventilation. But nobody is immune to heat. At 33–35°C with high humidity, little wind, heavy clothing, or physical exertion, heat stress can become dangerous even for people born and raised in the tropics.
Malaysia is a beautiful country, not just with warm climate throughout the year, but our people are warm (not hot), and friendly too - socially and culturally. Malaysia enjoys a diversity of cultures, ethnicities, religious and other system beliefs, with a fairly stable economy and social norms. Even our foods are warm, delicious and nutritious - everywhere - from homes, restaurants, small hawkers stalls to food courts.
The lesson from Europe’s heatwave is therefore not that Malaysia is safe from climate change. Malaysia is protected in some ways by the surrounding seas, frequent clouds, rain, and vegetation. But it is also vulnerable to rising humidity, heavier rainfall, flooding, urban heat, haze, and increasingly warm nights.
Nature has given Malaysia a maritime climate—a climate softened by oceans, clouds, rain, forests, and sea breezes. Europe has historically been cooler, but its cities, homes, hospitals, and populations were designed for a climate that is now changing rapidly. The terrible heatwaves now striking Europe are a warning that climate is not fixed. What was once rare can become frequent; what was once uncomfortable can become deadly.
Perhaps the greatest lesson is this: human comfort depends not only on temperature, but on humidity, wind, clouds, buildings, clothing, health, age, geography, and the way we design our societies. The sea cools Malaysia, the highlands offer refuge, sweat protects the body, and forests moderate the land. Yet all these natural protections must be respected and preserved in a warming world.
