Wednesday, March 17, 2010

The Trees are on Fire and she's fixing her hair: Tampines Wildfire.

Nicolette has been complaining about an odd burning smell she constantly wakes up to at Sembawang; and being the awful friend that I am, I told her its because Sembawang is too ulu (not that I'm in any position to say that because I happen to live in Jurong). Unfortunately, our friend and fellow Geography major, Li Shean proved my hypothesis wrong and informed us of the wildfire that has been taking place right below her block at Tampines St 72. As a student of Natural Hazards GE3231, she took pictures of the wildfire:

This is apparently not the first case of wildfire this year in Tampines. In fact, island-wide wildfire outbreaks this year has already hit record highs of 182 cases in January and 110 cases in the first sixteen days of February. I'm really quite bumped that I didn't witness any of these fires. 

Anyway, let us understand a little bit more about this wildfire phenomenon.

Wildfires, also known commonly as Brushfires in North America and Forest Fires in Europe, is essentially a natural phenomenon. No continent, save for Antarctica, is free from this natural event. The point I am trying to make here is that, it is not a hazard but a naturally-occurring event. It only becomes hazardous when lives are disrupted and properties are damaged. In fact, small Bushfires are positive events as they can actually add nutrients to soils. However, massive fires, such as the ones in Tampines have negative consequences on the environment, which we will discuss later. 

Another view of the Tampines St. 72 wildfire via stomp:

We are quite lucky, this is a  Ground fire or Surface Fire, which isn't too difficult to control. I mean, compare this with Crown Fires which are common wildfire types in South-East Australia and the Mid-West of USA:

So, how do Wildfires come about? Firstly, climatic factors play a significant role in wildfire development. The abnormally high temperatures and low rainfall in January and February this year has contributed to the development. From the figure below, Singapore lies in the Tropical Rainforest zone that is not usually wildfire prone. However, as it is confirmed that 2010 is an El-Nino year, this dry spell is here to stay, so peel your eyes for more wildfires this year! 

Wildfires, however, do not appear out of thin air - an ignition source is needed. They take the form of:
- Lightning strikes: contributes directly to 15% of the wildfires around the world, and Singapore has one of the highest rates lightning activity in the world.  

- Human activities: clearing of land (think: Indonesia wildfires), arson (e.g. vandals) and most importantly littering - of flammable materials and cigarette butts. So next time before you flick that butt into a bush, remember the possible consequence! 

So, other than the degradation of air quality - Nicolette's odd burning smell - which can bring about respiratory problems and discomfort to many; there are also other environmental problems associated with wildfires. Firstly, large fires destroys vegetation, organic materials and soils directly. The destruction of soils results in infertile lands, preventing future vegetation growth. According the Li Shean, the whole 'forested' area of Tampines St 72 is cleared. Also, soil degradation and the lack of vegetation will eventually result in increasing soil erosion, futher degrading the land. In extreme cases, this may happen:

All in all, Wildfires, especially in cities with sporadic vegetated lands like Singapore are often caused by human carelessness coupled with the correct climatic conditions (hot and dry). Thus, in light of the dry condition that is here to stay for a while, it is perhaps prudent for us to not ignite any wildfires by inconsiderate acts like littering and vandalism (in the form of arson)! I'm sure we are not the only ones annoyed at the horrible air quality!   


Special thanks to Miss Ng Li Shean for sharing her pictures with me : D

and oh, on a completely un-related note, we took Hobo down today from Sungei Kadut Industrial park. I'm proud to say it is the dirtiest sensor in the class. I'll upload the pictures from my phone when I figure out how to. Stay tuned for Singapore's Urban Heat island analysis (:

Friday, February 26, 2010

The Sun will be shining and my Children will burn: The Urban Heat Island. (I)

I apologize for two things, firstly for the lack of posts; and for the slightly macabre title. But I suppose all of us in Singapore can relate to it - the weather has been especially cruel of late, with yesterday's (24/2/10) temperature hitting 35 DegC. February 2010 could be the driest February (and probably one of the warmest) on record - rainfall is only half of February 2009. *sweats and melts*

My slightly-psychic-and-very-tall Urban Climates professor set us a project on the Urban Heat Island; we installed temperature sensors around different parts of Singapore, so if any of you guys see such stuff perched on a lamp-post innocently, please do not touch them (or take them down for that matter):

Before going into the details and purpose of the project, perhaps I should explain what exactly is an Urban Heat Island. Simply put, temperatures in urban areas are notably higher than those of rural, non built-up areas. This effect is especially pronounced 2 to 3 hrs after sunset. The nature of the built-material such as concrete and asphalt traps more heat in the day, and the urban geometry of high-rise buildings prevents this heat from leaving the urban environment, especially during nighttime (figure 1). 

Figure 1: The red arrows represent the heat released by the city, the urban geometry traps the radiation, making the city warmer at night. (yes I am absurdly free now HAHAH to have the time to make this diagram)

Also, lesser vegetation in Urban areas result in lesser evaporative cooling and hence, higher urban temperatures. Human activities also contribute waste-heat (cars, industries etc), but are secondary contributors towards the heat island phenomenon. When an area, especially the downtown core of the city (i.e. most built up), reveals a distinctly higher temperature than the non built-up areas, an Urban Heat Island is formed. 

The effects of Urban Heat island... well, I think we are all pretty familiar with them: 
- More intense human discomfort due to higher temperature - especially in the tropical regions (we are right smack in the middle of it)
- Higher possibility of Heat Waves 
- Higher energy consumption with the increase use of air condition

Singapore, being nearly 100% urbanized, is very susceptible to the Urban Heat Island effect. In fact, temperatures in the past - before rapid urbanization in the late 1960s - was nearly 7 DegC cooler than it is now (I read this somewhere, but I can't find the source now, will do so and upload it!). Thus, the nature of our project is to observe and compare temperature trends of different built-up areas in Singapore. Sensors were installed in HDB estates, Industrial parks and (hopefully) Green Spaces such as Lim Chu Kang and/or Bukit Timah.

My friend Nicolette and I, being the adventurous-we-like-to-give-ourselves-trouble sort, decided to install our sensor (which we christened 'Hobo') at Sungei Kadut Industrial Estate. For those who have no idea where that is, it is the stretch of scary-looking heavy industries you see on your way from Yew Tee MRT station to Kranji MRT station. 

Here's Hobo looking right at home in this godforsaken place:

Spot Hobo in this picture:

And here is a sneaky unglam pictures of me taken by Nic as I struggle to attach Hobo to its new home.  The very nice cabbie uncle decided to give us a hand. Oh. you may also notice the chair I lugged from Jurong East all the way to Kranji, but that's besides the point: 

Perhaps, you may be wondering what's the whole point of this study. But heat is a critical issue, especially so for Singaporeans and our rising electricity costs (I hear my dad screaming at the background). By collecting data, studying them and gaining further insights to such temperature trends, we (or maybe the government) can then come up with some solutions to this problem. On the broader scale, this can very well relate to all the climate change talks that has been going around. I'm not saying Urban Heat Island contributes to climate change - NO it does not, it is a local phenomenon. But it certainly does add on to the temperature stress that cities like Singapore is already facing with rising global temperature. 

So, stay tuned for updates about Hobo's time at Kranji. We will be collecting and collating our data in 3 weeks time. So, till then (: Meanwhile, please avoid taking any sensors down if you happen to see them around!

Love, Serene!

Special thanks to Miss Nicolette Ng for doing the whole Kranji thing with me (its your idea HAHAHAHA); and Mr Joey Kang for correcting my grammar mistakes!

Disclaimer: Climatology is not my forte, I welcome any corrections and/or critiques!