Thursday, April 14, 2016

Record temperatures in Bangkok this week?

Don Muang airport maximum daily
temps higher than 38C (102F) since 1951.
So how is Songkran, the hot season water festival week looking in regard to Bangkok hot weather this year ? Yesterday temperatures reached 39 degrees C (102F) at the old Don Muang airport, and the historical record I got from the Department of Meteorology shows that this is not a common occurrence, it happens in about 1 in 4 years over the last 65 years (1951-2013). But then, it is not all that special either, there are a fair number of readings over 39.5 and a few even over 40, especially in the late 1990s.

Do you see a long time trend in maximun temps at Bangkok here? I don't. But then, given the urbanization around the airport, which was surrounded by rice fields when I first arrived here in 1963, we should be surprised that there has not been a steady upward march of hot recordings over the past half century, even aside from any global warming, it having been known for a century that urban areas are generally warmer by 5 degrees or so than country areas.

So if we are looking for evidence of global warming in this record we are not finding it. It is worth considering that most of the records which people are using in this heated debate over temperature trends are also taken in and around airports. Do "climate scientists" pay much attention to microclimate?

For that matter if we are worried about human misery in the tropics, we should look at other weather indications like dew pount which better reflect our capacity to survive in hot weather. We die at dew points of 35 because we cannot dump heat at that level.

The southerly breezes in Bangkok were recently -- about 2 hours before -- flowing northward over the Gulf of Thailand, so along with local microclimatic ground heating from paving and other materials that capture heat, we should look to surface sea temperatures in that shallow gulf for explanations of downtown or airport temperatures.



Monday, April 11, 2016

Radiative cooling in the humid tropics II: special for psychrometriphiles

Today's entry is the second in an ongoing series on radiative cooling for the tropics and is mainly for readers who understand psychometric charts. I show today's very typical hot season trajectory of Bangkok air properties from dawn to mid afternoon (red arrow) superimposed on a handy old chart I use to aid my judgment on matters of thermal comfort.  The daily process is essentially isenthalmic (constant-enthalpy). Our Bangkok day is way outside of US standards of comfort (with which I disagree) and also within the "danger zone" (justifiably so) that was established by the US military after scandalous heat deaths of marine recruits during basic training. Having also done my basic training in the sweaty Virginia summer near Richmond, I am proud to have survived at least the heat battle of a forced march before reforms were instituted (but I recall an ambulance did trail our ragged column), though I never did hear a shot fired in Vietnam.

Today's Bangkok wet bulb temperature (surrogate for enthalpy) was 28C (82F). Wet bulb temps above 30 were recorded with deadly results in Pakistan last year and are considered very dangerous in military training. The wet bulb temp should be close to the surface sea temp (also 28 in the Gulf of Siam as recorded yesterday) and has never been seen to exceed 35. Wet bulb temps of about 32-33C have been recorded in Bangkok and also (surprisingly) in the middle of cornfields in Appleton Wisconsin. Our wet bulb today is about at the 1% summer design level for US hotspots such as Pensacola, Galveston, and El Centro.

Note from the chart that the afternoon and evening dew point temperatures drop to about 25C  and relative humidity to 50% so a cooled surface at that temperature would not attract condensation.

Sunday, April 10, 2016

Damp laundry in the morning heat

This hazy warm morning  at 7:30 am while checking my still damp laundry (high humidity at dawn) I measured a wet bulb temp of 28.2C (82F), as high as I can recall here in Bangkok. The daily pattern has been the same for a week now, typical hot season weather. Humid dawns with air, wet bulb, and dew point temperatures converging at about 27-28C, followed by warming  to about 38C (100F) midafternoon. Increasing relief from southerly breezes off the Gulf of Siam throughout the day and evening, offsetting to some degree the rising temperature. Much like late summer Gulf Coast Texas weather. Greater afternoon discomfort has more to do with glare and radiant heat from hot streets and sidewalks  than 100F air temperature. Average daily temps about 33C. Checking back over the years records I find that it was a bit warmer in the early 1990s, with daily average temps sometimes 34 or above, hence whatever people want to think we are not experiencing anything extraordinary so far this year. For the last week, check out this chart from Weather Underground (note the superelevated bump in dew point this morning):

April 2016, typical hot season, breeze from the south

Monday, March 28, 2016

Air conditioning, frat sex, and self reliance

These days the world thinks, mistakenly I believe, that it is high class to have air conditioning. Not always true, as an old Boston lawyer friend writes me:


My first experience with A/C was when I was employed during Law School as a clerk at a major Boston law firm, in the early 1960’s. The firm had no A/C generally although many of the Partners had individual units in their offices which then had windows that could be raised or opened in the Office Tower on State St  Boston. There was an obvious moral tone exhibited by several of the more Senior Partners who eschewed the individual units. On the opposite side having an  A/C unit was all but a necessity for the more Junior Partners to mark their newly acquired status in the firm. The library which served as my Office was a veritable oven, nevertheless I concluded that  the older lawyers  were basically right. Mick Jagger  (attendee – London School of Economics ) confirmed this essential truth to me 20 years later - “ You can’t always get what you want, but you may find out you have what you need “.

Old law partners learned
 to keep cool the hard way
The idea that it was once classier and a source of pride to not have air conditioning, as with these senior partners, is mostly forgotten and even unimaginable to the world, all the more so in upwardly striving Bangkok with its ethic of conspicuous consumption. It's a bit like boats without engines or wood coffee tables with ancient dents, burns, and saw marks which were once seen as far more distinguished than motorized yachts and that crappy plastic Euro furniture that people want in Asia now. 

But I'll bet those old Boston partners shrewdly figured out the offices that didn't get late August afternoon sun. This intelligent planning never occurs to anyone now and few apartment or condo buyers here in this part of the world ever think of sun exposure when they buy a unit. Just go ahead and pay a 300 dollar a month electric bill later. Hardly a sustainable way of life.

This reminds me of Camille Paglia's comments on the current date-rape campus hysteria. She says that girls once knew that it was not smart to walk around mostly undressed and drunk at 2 am frat parties. So now instead when they think the day after that maybe after the party they may have had sex with a frat boy while in a drunken stupor they are demanding a new layer of rape investigation and disciplinary adjudication to be dispensed by campus committees of students and professors as naive as they are themselves. The police and the courts, of course, wouldn't understand their pain.

Surely the decline of the traditionally powerful societies in the face of leaner and tougher people is in large part a loss of individual foresight and self reliance, an aggregation of expectations that the company or the employer or the state or the college will take responsibility for everyone's lack of foresight and mistakes in the face of reality.

Mango shower

Mangos on our deck at Ekkamai
Yesterday my wife brought a couple of nice fresh yellow mangos in from the big old tree that pokes through our deck at our teak house here in Bangkok, and sure enough last night we had our first mango shower which broke the recent hot weather and, as one of our local twitter wits points out, gave our poor air conditioners a rest. This mango showers is an old and romantic weather term used from India to Cambodia, I remember it from my early days in Thailand fifty years ago. It refers to small afternoon or evening rains that begin usually in March, come along every week or two, sometimes with a growl of thunder, and take the edge off the hot season which bears down on us at this time of year.

Sunday, March 20, 2016

Boston scorchers: will aircon strip away our best memories?

From the free download chapter
We are much inclined to think that air conditioning is a necessity, but I have to wonder these days whether this and much of the other technology said to be so wonderful is really important at all. One of the chapters in the book that was fun to write was my memories of those days old people in Boston used to call scorchers, though my mother preferred the ancient term dog days. On those canicules my grandmother would take me on the streetcar from her walk-up South Huntington Avenue in Jamaica Plain downtown to the Boston Common. I still enjoy looking at the details in this photo, the necktie, the newspaper. Was this man a bum? An unemployed veteran? If so, he made an effort to dress properly. Or was he just a lower paid adjuster from one of the insurance companies that dominated the skyline, lacking in those days even the first John Hancock building behind the Boston Common? 

To this day nothing beats the shade appreciated by this fellow, even here, in the tropics. Were they elms, those great feathery trees? From this same place you could hear the shouts of boys splashing about roughly in the Frog Pond.

Many of these most vivid memories serve as backdrops for the wonderful dreams that entertain my sleep these days, three quarters of a century later. They would not exist if the "benefit" of aircon had existed in those times, the mid 1940s. Will they now be as satisfactorily replaced by memories of sitting in air conditioned "family rooms" watching TV?

Thursday, March 17, 2016

Bangkok weather BS I: heat wave


We read today in our morning Bangkok Post how the temperature is going to be 41 (104F) today, with various Thai experts competing to explain why that will come to pass. No surprise to this observer that it is 33 with max 34 anticipated now at 11 am. Oh yes, it "feels like 41" whatever that means (it always feels like 41 when it's really 33 in Bangkok?)

Why this nonsense? The public discourse on weather and climate in Bangkok is becoming so foolish that it warrants a special series of posts here, beginning with this one, with some more coming up on such matters as the evidence for drastic warming in SE Asia, the coming drowning of Bangkok, etc.

I have a farm up in Isan, the elevation is about 200 meters. Last year my neighbor asked me if there was a danger of the sea reaching this height. 

You might think that only simple Asian peasants would think this way, but I can assure you that many of the people at a dinner party I attended last year in Atherton, California, richest town in the world, had pretty much the same idea.