thanks BFM for the current (updating) weather links from yahoo.
now, about the air quality readings provided lower down: what exactly are their criteria for good air? i fail to see how taipei and the rest of the west has been scoring ‘good’ or ‘very good’ readings when i can’t see 2km out of the window. (101 is about 2km away and i can only just see where it should be…)
does anyone know what the criteria are for clean and dirty air here? do they measure particulates, and do they break that down into size ranges? do they track nitrous oxides, sulfur and sulfur oxides, etc. ?
or do they simply count the number of cows in the air, and divide by 7? that would give a good reading all the time, except in typhoon season.
Yes, and you also you have to look at your particular area. When they say good that is taking the average reading of three stations. Out in Songshan conditions would be high on the moderate scale. Here in Muzha they are on the high good (nearing moderate).
Just click on the little arrow tag and it shows you exactly what the readings are for CO,02, 03, P12, SO2.
Click on the square over each reporting station and they break it down for you:
PM10(ug/m3) is probably particulate matter 10 microns or [color=red]EDIT: smaller[/color], measured in nanograms/cubic meter?
PM2.5(ug/m3) is particulate matter 2.5 microns or smaller, in other words, all that shit that passes right through your sorry-ass excuse for a scooter mask without even slowing down.
03 is ozone ppm
CO Carbon monoxide in ppm
NO2 are nitrogen oxides ppb
So2 is sulphur dioxide in ppb
This page looks to be out of date, but for what it’s worth… EPA website
[quote] POLLUTANTS STANDARD INDEX
To let the public understand the air quality more easily, the monitoring data is transformed to the Pollutant Standard Index (PSI). The monitoring data used to prepare the index is based on the criteria pollutants, which are : Particulate matter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO) and ozone (O3). For each pollutant, a subindex is calculated from a segmented linear function that transforms ambient concentrations onto a scale extending from 0 to 500. The PSI is calculated as the maximum of sub-index. The index range and descriptor category is as follows:
0 to 50…“Good”
51 to 100…“Moderate”
101 to 199…“Unhealthful”
200 to 299…“Very Unhealthful”
300 to above…“Hazardous”[/quote]
Thanks for the links. i mean, i know most of this already, i am just perpetually perplexed by why they claim the air is “Good” when i cannot see 2 km away. i can see smog dimming my view at about 100m or less today: i can see smog in the end of the corridor at work. to me, that translates as “Sucks”. the EPA website does not do a good job of explaining the scale they use: it seems like all the emphasis is on gasses, not particulates. they do not say how much of each category is included, and with what weighting, and how it is measured. is it a log scale? that would make the bad and really bad days crwd together, qnd allow them to say more days are Good. etc.
sorry for the rant, the air quality here is driving me nuts. (not the steering wheel in my pants. i am not a pirate.) for the sake of my lungs i am seriously thinking of moving back to Oz or NZ sooner rather than later.
Be thankful that you’re not living in Hong Kong, which has witnessed a rapid deterioration in air quality in the past several years. I also read that the air quality in Taipei city these days is about equal that of New York City.
i HAVE lived a sheltered life, i am discovering. or at least a clean-filtered one.
yeah, i have seen the air in HK, and cut it with a spoon. even more sad would be living inland from shanghai, or pretty much anywhere in the industrial belt in china. Yech… and that is mostly whjat we are breathing here, as it blows eastwards. it really does smell like a steel mill in taipei at night, but the steel mills are in eastern china.
good to see that the Chinese higher-ups are at least paying lip service to environmental issues like pollution, but it remains to be seen whether the lower-downs will fall in line. methinks the money lure is too strong…
problems were identified with the air pollution index calculations, where there is often a serious underreporting of the extent of the problem. this paper is an attempt to develop a new calculation protocol. doi:10.1016/j.atmosenv.2003.10.006
(Warning: some extra technical stuff follows!)
Revised air quality index derived from an entropy function
Wan-Li Cheng, Yu-Chih Kuo, Pay-Liam Lin, Ken-Hui Chang, Yu-Song Chen, Tso-Mei Lin and Ruth Huang
Abstract
The Environmental Protection Administration of Taiwan has provided air quality service by reporting the pollutant standard index (PSI) since 1997. This standard, developed by the USA Environmental Protection Authority, compares concentrations of the five main common pollutants (PM10, O3, SO2, CO, NO2). For each pollutant, a sub-index was calculated from a segmented linear function that transforms ambient concentrations onto a scale extending from 0 to 500. The standard index is based on the highest sub-index. The main disadvantage of the PSI is that it only identifies the levels of one pollutant at a time. Hence it cannot show whether more than one pollutant exceeds the daily standard level. A region may be regarded as polluted when the PSI scale reaches 100; however, this transformation can be misleading. For example, when the standard level for PM10 concentration reaches 125 μg/m3, it converts to a less significant value of 88 on the PSI scale. Confusion can also arise because the standard pollution concentration level varies among different countries. This paper discusses a more effective way of determining a suitable concentration level of pollutants in Taiwan.
Combining the original PSI with an entropy function, we can develop a revised air quality index (RAQI). The revised version can rectify the current deficiencies of the PSI. It considers the association of the five pollutants, and has the comparative index function. According to tentative results, RAQI should be representative, supplying the public with a better indicator of air quality.
