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!   

Love,
Serene!

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!

Sunday, November 22, 2009

Bonfires of Trust, Flash-floods of Pain: Bukit Timah Floods 2009

While revising for my natural hazards exam, LIM JIAYI (there i acknowledged you!) frantically told me to read the newspapers about the flooding event at bukit timah road on 19/11/09. I was a little skeptical about how big that flood can be, despite the crazily cold and wet weather this past week, due to the north-east monsoon.

Then, I saw this:

Sorry for my delayed reaction and initial skepticism, BUT THIS IS HUGE.

According to some NEA and PUB statements, from between 1.20pm to 1.50pm, 93mm of rain fell in the Bukit Timah area. That being equivalent 115 OLYMPIC -SIZE POOLS' worth of water. okay, to make another less sensational comparison, our average monthly rainfall is about 200mm. Thus, in 30 mins, HALF A MONTH'S WORTH OF RAIN drenched Bukit Timah.

Let's say we are in the 1960s, and Bukit Timah is all green, vegetated and unurbanized. The flood probably wouldn't have occured. Not on such a big scale anyways.

This is because the soils would have been able to take it the excess water, via a process known as Infiltration (#6 in the diagram). The absorbed-water will then flow laterally underground, through processes known as Throughflow, Interflow and Baseflow (#8 in the diagram), into rivers and streams. The underground flows are slow flows - it can take weeks for the water from the storm event to reach the river.



#6: Infiltration (water enters soil)
#7/8: Throughflow, Interflow, baseflow (lateral flows underground)
#5: Overland flow (self explanat0ry)

But with urbanization and concrete everywhere, infiltration is unable to take place, as concrete simply does not have the capacity to take in water. Thus, instead of travelling to the river by slow underground flows, water now travels through Over-land Flow (#5). Our drainage system helps dissipate the water, but when a storm event like 19/11/09 occurs, it overwhelms the capacity of the drain. This is thus, an Urban Flashflood event.

Ah, the poor Ferraris in the basements.

However, the thing that most people probably didn't pay much attention to is the colour of the flood waters. let's refresh our memory:



According to LIM JIAYI, and i quote, "This looks like Milk Tea."
Yes, it certainly does. Which begs the question, why does it look like milk tea????

It looks like milk tea because of the massive soil erosion that took place when the flood occured. And the eroded sediments were then transported by the storm waters.
This erosion problem isn't just limited to 'this prime residential area' (to quote joseph wong, some business man).

Take a walk by the fields next to Jurong East MRT station, in the NUS campus. It's almost everywhere. The worst case I've seen is probably along the stretch outside Toh Guan Dormitries. So maybe its a problem that the NEA should look into. Because soil erosion is a pretty big hassle, a lot of money probably goes into replanting grass at these area.

Its rather ironic if you ask me, some of the worst cases of natural hazards we have in Singapore such as this flood event often occur a long the 'prime' district. Landslides too, are rather common in Bukit Timah and Hillview area.

Jalan Dermawan (hillview) landslide 2007.

so as my jc teacher likes to say DON'T BUY HOUSES IN HILLVIEW! (HAHAHAHA)


okay back to revision!
love, Serene!

Monday, October 12, 2009

THANK YOU FOR SUPPORTING.

I AM VERY HAPPY.

because I AM ON THE READING LIST for a geography module offered in NUS, GE2229 (which i have taken last semester).

Please click to see picture (blogger is mad in all occasions):



can you believe this? because im still not over it.

I have to thank loads of people for this.
All my friends who accompanied me on such trips,
Chenko for his guidance and invitations,
TeamSeagrass, Ria (wildsingapore) and Koksheng (:

thank you all so so so much.
I will update soon after my crazy october deadline month.

Love, serene!

Tuesday, September 15, 2009

Are we Human; or are we Dancer?: Kranji Coastal Cleanup

Its hard to imagine just how horribly DIRTY our coasts are - the bits that do not look like grass/leaves are really Rubbish:


Jiayi and I signed up for the International Coastal Clean-Up Day (ICCUD) and went to Sungei Buloh to pick some mangrove trash. Seriously, our socialized conception of Sungei Buloh looks like this:


(source: http://www.freshbrainz.com/2007/10/sungei-buloh-wetland-reserve.html)

or


A clean stretch of mangrove for migratory birds to settle, for mudskippers to skip gaily about. Girls guides trekking through the path (as I did many light years ago) singing songs, not having a care in the world; families enjoying the clean fresh air....

well, what you did not see is this:



and this (which we named the styrofoam farm), which nearly made me tear my hair out:


These are the beings lurking quietly in the Mangroves. Beneath the leaf litter cover, hidden behind tall grasses... they are like the monsters under your bed, you think they aren't there, but they are. (okay sorry i just read this Neil Gaiman book so im still stuck with his way of writing HAHA)

The very brave Jiayi and I signed up to battle some marine trash. Tho' some of them may have drifted over from Malaysia, i believe part of the rubbish originated from singapore. For example, I discovered a patch of buried syringes and small empty glass bottles. No prizes for guessing what they were used for.

and the weirdest find of the day:


PLEASE THROW ALL RUBBISH (NO MATTER OF WHAT NATURE) INTO BINS. THE ENVIRONMENT THANKS YOU. (:

Here's us hard at work:




Which led me to another issue we grappled with on that day. There was a bunch of international school students working alongside with us from NUS. and what struck me was how comfortable they were with getting dirty. How dedicated and committed they were to picking up trash in the most obscure locations. Locations that no doubt will result in muddy shoes, t-shirts and shorts. such as:


John (thats really his name) braved the muck and looked as though he rolled around in the dirt. Look at his shoes:


While we, the NUS kids, stuck to dry, comfortable (although trash-filled) in-land locations.

also, the girls (even those with makeup on) have absolutely no problem with slinging bags of trash over their shoulders, even with the gunk dripping out of it. I just cringed at the thought of it. Can you bring yourself to do that?

in their dedication, they even uncovered a 'boat' and several huge chucks of car parts:


There is a quote by poet Hunter S. Thompson about how America is raising a generation of dancers. By implication, the western world is raising a generation that is soft, self-indulgent and reliant (sorry to all dancers, Ive been through about 2 months of dancing and i know dancing is TOUGH).

However, their behaviour at the Mangrove proved contrary... no? Are they brought up to be comfortable with getting dirty, with the outdoors? Or are we, singaporean kids (myself included), getting too soft and comfortable with our clean urban spaces?

This thought made Jiayi and I kinda sad for a while.

Nevertheless, it was fun! and I am challenging myself, from now on, to really get to know the outdoors.

Love, Serene!

Special thanks to Miss Lim Jiayi, for wonderful company and great discussions. (:






Monday, August 31, 2009

"Take nothing but Photos, leave nothing but Footprints"

Someone woke up at the ungodly hour of 5am to visit the Sentosa shore. Like me, he has an ulterior motive. Only, a more diabolical one:


We are not sure who he is, or what exactly he is doing. but from the looks of it, he is either collecting shells, or small marine creatures.


Do you know that when you pick up a shell, you are depriving a hermit crab a home? ):
This is one of the reasons why I did not want to reveal the place of this bit of shore.
With increasing numbers of visitors, this fragile stretch of Coral rubble may be abused and exploited (such as above).

I know it sounds awfully righteous of me to say this, but please, be responsible - throw your litter into bins, and when you do visit a place in nature, respect it.

Take nothing but photos, leave nothing but footprints (:
- Janette

love, serene.

Sunday, August 30, 2009

Everyone has Secrets, and this is mine: Sedimentary Rock Landforms at Sentosa

Ah, look! Someone (Marcus) caught me obsessively photographing the rocks:


I have to admit, I went to the Sentosa monitoring trip with a sly ulterior motive - I was dying to take a look at the Sedimentary Rock Cliffs and caves by the coast. I have to say, I was totally blown away.

Alright, before I go any further. Let me first explain what are Sedimentary Rocks. I know most people are probably thinking ROCKS ARE ROCKS, THEY ARE STONES. THE END. but NO! As I have previously harped about, rocks are really records of the Earth's geological history. These historical records can be divided into 3 main groups:

1) Igneous Rocks - Rocks form when volcanic lava cools E.g Granite
2) Sedimentary Rocks - Rocks which are depositions of other eroded materials, and overtime get cemented together E.g Limestone
3) Metamorphic Rocks - Rocks which are formed under intense heat and pressure E.g Marble

So, the cliffs at Sentosa are Sedimentary in nature, namely, they are made of Sandstone:

notice the 'layers' that seem to mark the cliff, this is a characteristic of sedimentary landforms (pls click to enlarge, small pictures dont do these magnificent landforms justice!!!!!!!!!!!)


Also, notice that the cliffs are often bare and un-vegetated. This shows that the erosion processes, driven by the wave actions, are very active. Hence, this part of the island is actually receeding inwards, even now as I type!

A view from the shore:


some of us have the impression that cliffs are like:


(http://www.irishdancingorg.com/)

These cliffs are what I call "geologically mature" cliffs. They go through millions of years of weathering and erosion. and just look at the size of the waves in this above picture, its difficult for Singapore waves to possess THAT much energy as we are surrounded by the Indonesian archipelago. Thus, our cliffs are relatively small, but no less special, as compared to the above.

Who knows, maybe with the tectonic shifts in the region, the cliffs at Sentosa could be like that in 20 million years! (:

anyways, back to my point - here are some observations i made about the cliffs:

(disclaimer: due to the appalling lack of academic literature about Sentosa's Cliffs, these observations are NOT cross referenced)


#1 Can you see that the rocks are kinda tilting in one direction? To help you see, i've drawn some very straight (ahem) arrows on the close up below! This means that the rocks are arranged in such a way that they are Landwards dipping.

This makes this side of the cliff fairly stable - meaning there will hardly be events like Rockfalls or Avalanches. This postulate is supported by the fact that there are no rock debris at the bottom of the cliff.

#2 THERE ARE NATURAL-CAVES IN SINGAPORE:


These caves form at the base of the cliffs, and these are the weakest areas of the sandstone. What do i mean by weakest?? meaning they are the most severely jointed area i.e. they have the most lines of weakness for water to penetrate and weaken the internal structure! such as:


see all the lines and cracks? There's actually a small cave in the making in the pic, try to spot it!

I wanted to duck into the caves for a look, but i was told gigantic spiders lodge in there... *BACKS OUT INSTANTLY* HAHAHAHA. maybe next time (or not).


Lastly, landslides are not uncommon at this side of Sentosa! I love this retaining wall, for some weird reason, it blended right in with the coastal landscape. i almost missed it! Behind it is a bunch of weathered material, clay probably, from the looks of it.

Well, there you have it. Despite the multiple and rather obsessive coastal reclamation (Labrador beach is the ONLY natural stretch in our Southern Coast), these beautiful cliffs remained untouched and often unnoticed. The date of this ONLY bit of graffiti state FEB 1979.


I would hate to think about the day when the government decides that one IR on sentosa is not enough, and this undeveloped bit gets reclaimed as well. Or worst still, this part gets commercialize and becomes part of the STB marketing scheme. so, before all that happens, i hope that my little blog post about this relatively unknown side of Sentosa has opened some of your eyes (:

this is our geological history!

Love, serene!