That short spell of "cool" weather in Singapore...

Okay, I've just done a really serious post - so let's do a silly one to put a smile on your faces! Singapore was in the news recently because of a spell of cool weather with temperatures dropping to a low of 21.2 degrees in Northern and Western parts of Singapore on the 14th of January, the lowest temperatures recorded since 2016. Well, that's just two yeas ago, so such temperatures aren't that uncommon. Now whether or not that seems cool depends on what you're used to - I usually smirk with disdain when I read the Facebook posts of my Singaporean friends when they make a fuss about the 'cool' weather because I live in the UK where the lowest temperature recorded last weekend was -13.5 degrees in Dalwhinne, Scotland and we had some snow this morning. I rushed upstairs in my shorts and did a video for Instagram of the fluffy white snow falling - so forgive me if I fail to understand how you can find 21.2 degrees even vaguely cold when it is snowing in London today. The low 20s is below average for Singapore, that's for sure: but when people start using words like chilly, cold or winter, that's when I have to react with, "aiyoh, you suaku or what? Have you ever experienced a real winter? Have you ever left Singapore? Or are you having a fever, how can you find 25 degrees cold?"

But putting my cynicism aside, let's talk about the cool weather in Singapore. The fact is Singaporeans love air-conditioning and everywhere from the offices to public transport to shopping malls to cinemas to most homes are air-conditioned and so that should mean that experiencing a temperature of 21 to 23 degrees in Singapore is really something Singaporeans experience all the time - except of course, they have come to expect this kind of comfort whilst indoors rather than outdoors. My sister told me that it did make activities like jogging a lot more pleasant, but you would have to contend with the rain. So whilst it does make a pleasant change from the usual sticky, unbearably hot and humid Singaporean, I roll my eyes in disbelief when I see photos of Singaporean aunties walking down the road in winter weather when the temperature outside is about 25 degrees. Those low temperatures quoted in the headlines only lasts a brief period in the pre-dawn hours then it gets back up to at least the mid-20s by the time the sun rises - so you remember that photo of that Chinese lady wearing a red puffer jacket at Marina Bay? That was taken in the day time, so the temperature at that time would be around 25 degrees at least, if not higher. I have a similar jacket in blue, but I would only wear that when the temperature drops below 10 degrees - surely she must have been sweating buckets in that coat!

Here's the thing that leaves me somewhat confused: yes I know many Singaporeans are rushing to get their winter wear like sweaters, coats and boots out because they think they can finally wear them. Those items have probably been collecting dust somewhere in their closets for a long time - however, that just sends out the wrong message. These people are trying to send out the message that they are rich, cosmopolitan and atas enough to own some rather nice winter wear: they can't wait to show it off and flaunt it. However, that plan would work well if you did have a cold snap like they experienced in Bangkok back in December when temperatures actually fell to 14 degrees. We're talking about day time highs of 25, 26 degrees in Singapore - that's no where near cold enough to even justify any kind of winter clothing, not even a light sweater. Surely if you wanted to show off that you're so cosmopolitan and well-traveled, the right response would be to smirk and say, "26 degrees is a heatwave in London. I don't suppose you have ever experienced a north American polar vortex have you? That's when you have a meter of snow outside your house and that's when you actually need winter wear. Putting on your boots and coat when it is 25 degrees just tells me that you're too poor to afford a proper winter holiday. Have you even been skiing? I was in Stockholm just before Christmas now that was really cold!"

But okay, okay, you're going to tell me that auntie is not used to cooler weather, but if she actually has a jacket like that, then that suggests that she has traveled to cooler countries before. If that is the case, then surely she should be used to air-conditioning in Singapore? I have a big house in London now and when I used to live in a much smaller apartment, I could afford to keep the house really warm and it would be about 24 degrees in the flat. But now, if I were to heat my whole house up to 24 degrees, then I would pay a lot in heating bills. So the temperature of my house varies, depending on the outside temperature but usually it is around 18 to 20 degrees and I am very used to that to the point where I am walking around in shorts and T-shirt all the time, as if I was in Singapore. But can you actually feel cold at 25 degrees then? Well, the fact is yes: you can feel cold at any temperature if your body is sending confusing signals to your brain. The classic example is when we have a fever, our bodies are deliberately trying to raise our body temperatures to fight infection by speeding white blood cell production and slowing bacteria reproduction. So you could be sitting in a desert where it is 40 degrees, but if you have a fever, your body would still deliberately send signals to your brain that you are cold despite the fact that you're clearly not. Likewise, old people with very poor blood circulation can feel cold easily, that is because their hearts are weak and unable to pump the blood around their bodies efficiently enough - that's when they start experiencing cold in their extremities like their ears, fingers and feet. This kind of cold has nothing to do with the room temperature, but is indicative of a problem with their circulatory system, that's why older people tend to feel cold.

Likewise, you don't need the temperature to be high to feel hot. When I was skiing in the Sierra Nevada mountains last week, I was sweating profusely despite the fact that it did drop to -18 with wind chill at one point. Yes you can sweat profusely when it is -18 as long as you are doing a lot of exercise and skiing in very hard work. That is why I always try to wear the minimum I can get away with when skiing - I may feel quite cold first thing in the morning, but I know I will be a lot happier once I start skiing. By the same token, you don't need temperatures to be low to feel cool: all you need to do is to confuse your brain. My sister lives in a lovely condo in Singapore which has a pool that she refuses to use because she claims, "no, that water is too cold". I have done the maths: the air temperature is about 31, 32 degrees and the water temperature is about 27, 28 degrees. There is about a 3 to 5 degree difference between the water and air temperature at her pool, so when you initially step into the pool, the water feels cold because it is cooler than the air by 3 to 5 degrees. You may even shiver a little as your brain takes a moment to get used to the water temperature - that's when my sister jumps out of the pool, grabs her towel and declares the water too cold. However, all you need to do is keep your body submerged in the water patiently for just a few minutes and then your brain will realize, actually the water is not cold at all, it is relatively cooler than the air but it is not cold. Water temperature tends to change a lot more slowly than air temperature, so if you were to step into the same pool in the pre-dawn hours when the air temperature is say 22 degrees and the water is 5 degrees warmer at 27 degrees, it will feel pleasantly warm even though the water isn't heated - it is just your brain playing tricks on you and thus all you need is a bit of scientific knowledge to understand what is going on.

How cold will that water feel when you jump into the pool?

A lot of Singaporeans play the "oh I am not used to cold weather, I live in Singapore" card - but even then, I can find examples to disprove the fact that their bodies cannot tahan cold weather. The worst case of this was when this woman came to my blog for advice on winter weather, she was going to Japan in winter and visiting a part of Japan where there would be snow. She actually asked me if it was safe to touch snow, as she didn't want to get frost bite. That was my face palm moment - I had to point out to her that the temperature of your average freezer is -18 degrees. Yes, that means that everything in your freezer from your ice cream to your frozen chicken to that bag of frozen peas are chilled down to -18 rather than just 0 degrees. Do you put on your gloves before reaching into your freezer to pick up a pack of fish fingers or a tub of frozen yogurt? No, we're quite happy to handle very cold frozen objects in our kitchens or a supermarket, the snow you're going to touch in Japan is unlikely to be -18 degrees cold, unless the air temperature is also at -18! Likewise, we are quite happy to ingest food at -18: ice cream fresh from the freezer is at -18, that's actually really cold but do we complain? No, we only complain if the ice cream is already melting as it approaches 0 degrees, we like our ice cream to have a certain texture that it can only maintain when between -18 and -12, any warmer than -12 and it starts to get too soft! I bet you this woman would gladly enjoy her ice cream served at -18, yet she doesn't dare touch snow at like -5?

So how cold can it realistically get in Singapore? Well, not very is the answer. There are too many factors to keep Singapore constantly hot: firstly, you're so close to the Equator that means you're going to get 12 hours of hot, tropical sunshine a day and that's going to keep you hot all throughout the year. Think about the folks in Reykjavik who get about 4 hours of sunshine a day during Christmas time, the sun rises at about 10:30 am and sets at 2:30 pm - the nights are very long in Iceland during winter, without the warming rays of the sun, it can get bitterly cold there. The other major factor is that Singapore is an island, surrounded by the warm waters of the South China Sea and the Straits of Johor. Water is very good at holding heat - so the water in the seas around Singapore absorbs the heat of the sun during the day and it retains that heat during the night, so the island effectively is taking a nice warm bath every night and you don't get cold in a warm bath. Staying with the sea water, there is a lack of currents around Singapore given its very sheltered location, with Peninsular Malaysia, Java, Sumatra and Kalimantan blocking any more direct exposure to ocean currents. Compare that to the coast of Chile, Peru and Ecuador which is affected by the Humboldt current, bringing much colder water from the south Pacific - sea surface temperature off the coast of Peru can be as low as 16 degrees when other regions along the same latitude not affected by this cold current typically record temperatures of around 25 degrees. That's never going to happen in Singapore with your calm seas, trapping all that heat in the waters around Singapore.

That's me in Austria - when I really needed winter wear!

There's another factor as well, the lack of mountains. The highest point in Singapore is Bukit Timah hill at just 163 meters, that means that the highest elevation you can reach in Singapore is actually the top of Tanjong Pagar Centre skyscraper at 290 meters. That whole area of Tanjong Pagar is so near the sea, the skyscraper was built on land barely a few meters above sea level, so let's say you get to the top of that skyscraper, is it enough to have an impact on the temperature? Yes actually: this is known as the lapse rate: the rate which temperature falls with altitude. Generally for every 300 meters you ascend, the temperature should drop about 2 degrees, variables like cloud cover, dew point temperature, relative humidity, wind speed and direction can play a factor. So from the top of Tanjong Pagar Center, you can expect it to be just under 2 degrees cooler than the surrounding areas. 2 degrees may seem a lot to you guys in Singapore, but think about Malaysians who have Mt Kinabalu which stands tall at 4,095 meters, frost and snow happens regularly during winter as night time temperatures can easily fall to -5. The tallest building in the world is currently the Burj Khalifa in Dubai, even if you stood on the very top of that 828 building (more than double Tanjong Pagar Centre), the temperature up there is about 5.5 degrees cooler than at the ground floor, even if you did have a building that tall in Singapore, it still wouldn't be tall enough to produce the kind of conditions you'll get at the top of Mt Kinabalu in Sabah.

The spell of cool weather in Singapore was caused by the 'monsoon surge' - but here's the problem: Singapore is a very long way south from the source of the cooler air. At this time of the year, the monsoon draws cooler air comes from a long way north, from North East Asia where the air is a lot cooler. But that's very far away, Taipei is a 3,250 km from Singapore - by the time that cooler air is driven over the warm South China sea, it gains a lot of heat and has become a lot less cold than it was when it was hovering over Taiwan. Bangkok had a cold spell back in December when temperatures fell to 14 degrees - yes Bangkok can get a lot cooler than Singapore, all you need is a gush of cold air to come from Yunnan or the highlands of Myanmar to flow south to Bangkok. In fact the lowest recorded temperature in Bangkok is just 9.9 degree because that cold air needs to travel as little as 500 km and it is over land, rather than sea. Let's look at the case study of Belem in Brazil which has a latitude and climate similar to Singapore's - however, the lowest temperature on record in Belem is 14 degrees, that's a lot lower than what Singapore experienced this January. The reason why the temperature in Belem can fall that low is the same as in Bangkok - there is a direct overground route for cold air to reach Belem directly from the interior of Brazil whilst Singapore is just surrounded by so much warm sea.

There is only one scenario which will truly make the temperatures in Singapore plunge, it is extreme but interestingly enough, it has happened before. In 1883, the volcano Krakatoa erupted with such force that it was one of the most deadliest volcanic eruptions in history, killing an estimated 120,000 people in total. The volcanic eruption sent so much ash into the skies that it altered global climate patterns for five years. Krakatoa spewed so much ash into the skies the ash was spread around the world by air currents, but note just how close to Krakatoa Singapore was. Singapore would have definitely been covered by a significant amount of ash by that eruption then and for many months, the skies would have been obscured by that huge amount of ash in the air. You think the haze caused by the Indonesian forest fires are bad? The ash from that volcanic eruption was so much worse and no amount of rain could wash it away for years. Records were not kept then (remember this is 1883 we're talking about), but it would have been interesting to see how low the temperatures in Singapore fell when the warming rays of the suns were blocked from reaching the land by those ash clouds that stubbornly hung over Singapore for many months. It was estimated that global temperatures fell by about 1.2 degrees in the summer following that eruption, but local areas near the volcano (such as Singapore) would have been far more severely affected. Mind you, there are still many active volcanoes in Indonesia today! So if an eruption of a similar scale happened today, it could potentially keep temperatures quite cool for a few months or even years. But let's hope it doesn't ever happen in our life times given the kind of devastation such an eruption on that scale would cause!

Okay, I hope you've enjoyed reading about this short piece about the cool weather in Singapore. What do you think? If you're in Singapore, is it really that cool or is it all a bit of hype? Are people really wearing sweaters and boots on Orchard Road when it is 25 degrees? At what temperature would you wear a winter coat? And don't forget people, there's always Snow City in Jurong if you're really desperate for a taste of winter but can't afford to fly to somewhere like Mongolia, Finland or Canada. Let me know what you think please, do leave a comment below. Many thanks for reading!