Saturday, September 13, 2008
Sep 2, 2008
Sea level 'rising faster than thought'
Rapidly-melting Greenland Ice Sheet spells danger for coastal cities: Report
PARIS: Much of the world's coastline may be drowned by rising seas sooner than anticipated because scientists now say they cannot rule out a fast-track melting of the Greenland Ice Sheet - a prospect once the preserve of doomsayers.
This would spell trouble for Singapore and many countries in the world.
The new findings, just published online by Nature Geoscience, warn that the current pace of the melting ice sheet in Greenland may have been seriously underestimated.
The researchers drew their conclusions after comparisons with the swifter- than-realised demise of the Laurentide Ice Sheet during the last Ice Age, which took place after a spurt in warming. That event smothered much of North America.
'The word 'glacial' used to imply that something was very slow,' said climate researcher Allegra LeGrande of New York's Columbia University, who was not part of the research team.
'This new evidence from the past, paired with our model for predicting future climate, indicates that 'glacial' is anything but slow. Past ice sheets responded quickly to a changing climate, hinting at the potential for a similar response in the future,' the researcher said.
Seeking help from the past, geologist Anders Carlson at the University of Wisconsin led the team that delved into sediment left by the Laurentide Ice Sheet.
At its apogee some 20,000 years ago, the Laurentide was 3km thick. Then a big warming occurred, apparently caused by a slight orbital shift which increased radiation that the Earth received from the Sun.
Dr Carlson's team calculated that the Laurentide had two bursts of very fast melting before it finally disappeared about 6,500 years ago. The first phase, around 9,000 years ago, drove up sea levels by around 7m, at a rate of 1.3cm each year. The second, around 7,500 years ago, accounted for a rise of 5m at the rate of 1cm annually.
The latest discovery has raised worrying questions about the future stability of Greenland's Ice Sheet, since a spurt in warming will be mirrored once more by the end of this century, scientists say.
The researchers caution that Greenland is an island bathed in chill water, has a somewhat different geology from that of North America, and so the timetable of the Laurentide's break-up may not exactly apply to it.
Even so, the upper range of the Intergovernmental Panel on Climate Change's (IPCC) temperature estimates at century's end are in line with those of the naturally-induced warming that doomed the Laurentide, they said.
The IPCC had predicted warming of 1.8 to 4 deg C over the century.
Although scientists are confident the mighty store of land ice on the Antarctic has so far escaped major damage, they are far less sure about Greenland, whose ice sheet holds enough water to drive up sea levels by 7m.
In addition, the Greenland Ice Sheet is far smaller than the Laurentide was and thus lacks frigid bulk to help shield off warming.
'We have never seen an ice sheet retreat significantly or even disappear before, yet this may happen for the Greenland Ice Sheet in the coming centuries to millennia,' said Dr Carlson.
In a commentary, published in Nature Geoscience, scientists Mark Siddall and Michael Kaplan said Greenland's glacial slab was entering into a temperature range at which it was becoming 'particularly vulnerable'.
'The (new) work suggests that future reductions of the Greenland Ice Sheet on the order of 1m per century are not out of the question,' they said.
AGENCE FRANCE-PRESSE
The Ilulissat Icefjord, in western Greenland, in a picture taken in May. New findings by scientists show that Arctic ice levels have dropped sharply due to global warming, with the extent of sea ice dipping below the 2005 minimum. -- PHOTO: AGENCE FRANCE-PRESSE
WHEN THE ICE SHEET MELTS...
• Rising sea levels would spell catastrophe for 136 port and delta cities around the world.
• Up to 150 million people in the big coastal cities are likely to be at risk from flooding by the 2070s - more than three times as many as now.
• Of the 10 most exposed cities, nine are in Asia. These are Bangkok, Dhaka, Guangzhou, Haiphong, Ho Chi Minh City, Kolkata, Mumbai, Shanghai and Yangon.
• Cities most at risk of catastrophes, in terms of exposed population, are Guangzhou, Ho Chi Minh City, Kolkata, Miami, Mumbai, New Orleans and Shanghai.
• Singapore could see coastal erosion and flooding, destruction of mangrove swamps and submerging coral reefs fringing the offshore islands.
• Sea water could enter Singapore's coastal reservoirs, such as Kranji, Sarimbun and Seletar, making the water undrinkable.
• Commercial areas around the Singapore River, parts of the west coast, parts of Changi Airport and a major part of the recreational land along East Coast Park will also be more vulnerable.
• To avoid major catastrophes in Singapore, flood-alleviation projects have been undertaken. Roads have been raised and drains enlarged, a move which will cut down flood- prone areas by more than half in 2011.
AGENCE FRANCE-PRESSE, REUTERS
[tommy] [3:05 PM]
Wednesday, July 30, 2008
The Ess Army together with studenst from class 4J decided to plant some trees in a field in the school.
Our school hall has been air-conditioned this year so that we can have a condusive climate to do our examination.
We see the need to plant more treess so that we can reduce the carbon foot print of the air-con hall.
Stay tuned as we report on the progress of our garden
[Mayflower] [3:44 PM]
Wednesday, July 16, 2008
After our presentation at the Worldview 360, we are very grateful and thankful that so many students and teachers have given us so many valuable feedback.
This has set us thinking and motivated us to go into further research.
According to the U.S. Environmental Protection Agency, Oil of Citronella has been used for over 50 years as an insect repellent and as an animal repellent.
It is found in many familiar insect repellent products: candles, lotions, gels, sprays and towelette wipes.
These products, which vary in efficacy, repel various insects, some of which are public health pests, such as mosquitoes, biting flies and fleas.
When used according to the label, citronella products are not expected to cause harm to humans, pets or the environment.
Please go to the website below to read up for more information.
1.
http://www.epa.gov/oppbppd1/biopesticides//ingredients/factsheets/factsheet_021901.htm2.
http://www.epa.gov/oppsrrd1/REDs/factsheets/3105fact.pdfHere is a project entitled "The Effectiveness of Lemon Grass as a Natural Mosquito Repellent"
1.
http://www.usc.edu/CSSF/History/2004/Projects/J1408.pdfThe purpose of this experiment is to determine if Lemon Grass is an effective mosquito repellent compared to a DEET-based bug spray. The hypothesis states: Lemon Grass is an effective alternative mosquito repellent for people sensitive to the DEET compound (Diethylmetatoluamide).
According to the The Cancer Awareness Coalition (CAC)
the mission of the CAC is - to raise public awareness about the health risks associated with pesticides and other environmental toxins - to encourage growers, homeowners, and others to use more natural products - and to promote legislation designed to protect public health.
Please go to this website to see the problem with DEET
http://www.cacinfo.org/DEET.html(P.S. There are many ways to give feedback. We aim to received them with a positive attitude even when feedback is given in a negative tone.)
[Mayflower] [3:38 PM]
Sunday, July 13, 2008
The war has only begun. Fighting climate change is not a short term battle but a lifelong war. After wining the Worldview 360 for the Best Overall Project and the most creative presentation, the
ESS army is back to
the drawing block for our next project.
We plan to use the prize money that we have won to built a garden in our school. We plan to plant some native trees and
shrubs to reduce our own carbon footprint. Another class (4J) has agreed to join us in this project and they will also plant two trees in the garden.
We hope that this garden will inspire our school mates to fight
climate change by reducing their carbon footprint.
In addition, we will also plant
pandan leaves and lemon
grass to promote the use of natural insect repellent instead of those which we can buy from the supermarket.
Fighting climate change is not a once off event to be forgotten after a competition but is a lifestyle change which involves forming new green habits that will reduce our carbon footprint.
Here are some information about lemon grass which is one of the main ingredient for our Shoo Mozzie
Lemon Grass, Ginger Grass, Serai Grass
Cymbopogon Citratus
Description
Perennial, densely tufted, aromatic grass.
Stems underground, short, whitish or pale-violet.
Leaves in dense clusters, linear amplexicaul, rough-margined, glaucous green on both sides.
Inflorescence in many-branched panicles without stalks.
All parts of the grass are lemon-flavored.
Chemical Constituents
The whole plant contains an essential oil consisting of critral, limonene, isopulegol, citronellic acid, geranium acid and a-camphorene.
Uses
The entire plant possesses antiseptic, antiferbrile and stomachic properties.
It is used in treating coryza, influenza and pyrexia.
It is also prescribed against dyspepsia and vomiting and as a carminative, using three to four drops of the essential oil, diluted in water.
Used externally to treat eczema.
The essential oil is used as an insecticide against mosquitoes and as a deodorant.
(P.S. We are greatly touched and inspired by the suggestion provided by one of our friendly competitors that we should test out our Shoo Mozzie by using actual Aedes Mosquitoes as part of a scientific studies.
We regret to say that after consulting with relevant authorities, we could not get permission to breed them as the slogan says: "If they breed, we will bleed."
If any one of the mosquitoes is released into the environment, it will be a bio-hazard.
Thus we will have to rely on secondary sources to test out the effectiveness of our product.
Nonetheless, we discover that sometime our grandmothers' old wives' tales hold more than a grain of truth and we will learn to respect this pool of native knowledge rather then solely on scientific studies alone.
But thank you for taking the time to suggest this test. )
[Mayflower] [9:19 AM]
Thursday, July 10, 2008
The
Ess Army has done it. At the World View 360 the
Ess army was awarded two
awards : the most creative presentation award and the best overall project award.
The competition was held at the Science Center on 10 July 2008.
After the competition, the guest of honour Dr Amy
Khor took a picture with the
Ess Army.
This is the display board that we made for the competition.
Our mascots with the trophies.
Well done. Of course, this is just the beginning and there is a lot of work to be done.
[Mayflower] [10:22 PM]