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Monday, November 21, 2011

Speaking of science - E-mails not all that ‘green'

During Deepavali time, these days, we are inundated with electronic greeting cards, and we too send several such e-cards ourselves. We believe that by switching from paper to electronic mode of communications, we are “green”, and that in doing so we have saved paper and thus done a bit to save the environment and generate less CO2

Well, perhaps just a bit but it appears not as much as we are led to believe. “E-mails are not so green” reports a news item in a recent issue of the journal Science.
The often-quoted estimate by Mr. Matthew Yeager of Computacentre (Europe's largest IT infrastructure company) claims that sending an e-mail attachment of 4.7 megabytes (MB) creates as much greenhouse gas as boiling a tea-kettle 17.5 times. 

His study claims that an e-mail of 1 MB would be the equivalent to the emission of 19 grams of CO2 And if that mail is copied (cc'd, as we type) to 10 people, its impact is 73 grams of CO2
Well, I was astonished to read this, since I too believed that I was saving the planet a bit by using my PC to communicate with people, instead of “snail mail”.
Keira Butler explains the matter in an issue of the magazine The Atlantic (August 12, 2010). She says “Say you send a picture to 20 people by email.
Each one has to download it. That means the use of equipment such as personal computers, servers, storage centres (not to mention printers for hard copy, if used)”. All these cost energy and hence more CO2 emission.
It is a matter of scale. Matthew Yeager points out that the current amount of data storage across the globe is 1.2 zettabytes (ZB) of stored data. This requires equipment with a mass equivalent of 20 per cent of the island of Manhattan, New York City! Put another way, this level of stored data is the equivalent of all of the US' academic libraries multiplied by half a million! And the data storage is expected, by the year 2020, to grow to 35 ZB (incidentally, zetta is a sextillion, or 10 raised to the power 21 (or 1 followed by 21 zeros).
The scale increases thousand-fold each time from million or mega, to billion (giga), trillion (tera), quadrillion (peta), quintillion (exa), sextillion (zetta), septillion (yotta) and so forth).
E-mail is thus not all that green. And e-mails with attachments are worse. Yeager estimates that in a 100-people company where each employee sends on average 33 e-mails a day and receives 58, the greenhouse gas emission linked to emails would be around 13.6 tons of CO2 per year.
And a study by the French government's Environment and Energy Management Agency (Ademe) suggests that if each of these 100 employees sent 10 per cent less emails for a year, they would save CO2 emissions equivalent to one round-trip flight between Paris and New York.
Talking of CO2 emissions by airline traffic, I was reminded of what Dr. Jeremy Nathans of Johns Hopkins wrote to me (by e-mail, not snail-mail) when we invited him to come to Hyderabad for delivering the Champalimaud Lecture in 2009.
He declined coming in person, stating that he is doing his bit to the environment by not flying all the way from Baltimore and back. We had him lecture electronically (video talk real time; I should now estimate how much CO2 he would have saved by not flying but video-lecturing).
To get an estimate of how much power is consumed by electronic communication, go to the website http://whatsthisgottodowithstoragefiles.wordpress.com/2010/08/wired-uk-july-2009-internet-electricity.pdf.
They point out that 30 per cent of the input power in each computer is used in powering the chips, 30 per cent of the energy entering a microprocessor is turned into heat, and that 123 billion kilowatt hour (kwh) per year is how much electricity it takes just to keep the Internet's servers running.
And traditional IT environments, says Yeager, tend not to be overly efficient in scale. Traditional infrastructure — server plus storage plus network plus operating system plus application — all lead to wastage in efficiency. Combine this with what Keira Butter points out in The Atlantic, you get an idea of how much energy is lost in electronic communications. Yes, e-communication does save trees, is more efficient and produces less CO2 than paper-based communication. But the scale of it is what needs to be kept in mind.
Take Facebook usage. It is estimated that its users alone are uploading over 1000 photos per second, or 3 billion photos per month. Recall the tea kettle boiling equivalent of sending a 4.7 MB attachment, and you get the idea. 

What should we do?
So what should we do? There are several ways of saving energy and cutting down greenhouse gas from our end. First, free up the memory space in the computer. Clean up the e-mail box (in and out mails) periodically. Not doing these means greater demand for storage and energy used by that storage.
Second, limit the number of recipients for each e-mail (cut down the number of cc's to).
Third, cut down the size of the attachments (boil less tea- water).
Fourth: enter the URL address directly rather than use a search engine. Cut down the times you “Google”, “Yahoo” etc.
Fifth: don't leave your computer and accessories on overnight (as many offices do), not even on ‘ sleep mode' (even if that eats up only 1-10 watts).
Sixth: laptops use 15-60 watts while desktops use 250W. Cut down the power by doing more ‘offline' work than online. Finally, remember Facebooking and Twittering burn carbon and make CO2. Talk more and twitter less!
dbala@lvpei.org 

Thanks: www.thehindu.com - 10.Nov.2011
http://www.thehindu.com/sci-tech/energy-and-environment/article2612323.ece

 

Yoga vs. regular exercise


Naturopath S R Jindal believes the benefits of yogasanas are manifold and that they score over physical exercise. He lists why yogic exercise is the better option
    Thyroid Patanjali’s Yoga Sutras describe asanas as “sthiram sukam
asanam”, meaning a body position that is “steady, calm and comfortable”. Physical exercise, on the other hand is an activity that works our muscles and needs energy. It is different from yoga asana. Here are the differences:

1 | Physical exercise consumes more oxygen than yogasanas.
2 | The heart has to work harder during physical exercise, but BP and heart rate decrease when you practise asanas.
3 | Physical exercise can overwork joints and even cause rheumatism and stiffness later in life. But asanas encourage flexibility and build stamina.
4 | Physical exercise builds up toxins in the body while asanas eliminate them.
5 | Generally, physical exercises are done quickly causing heavy breathing. Thus the respiratory system is forced to work harder.
6 | Most types of physical exercise develop muscles. The larger the muscle, the more nutrition and oxygen it needs. This means that the organs will get less nutrition and oxygen. Asanas reverse this. They enable the organs to get the greater share of oxygen and nutrition.
7 | Those who practise yoga need less food compared to those who engage in physical exercise.
8 | Unlike exercise, asanas are practised slowly with relaxation and awareness. Asanas balance emotions and help develop a positive attitude to life.
9 | In yoga, body temperature drops, while in exercise, it rises.
10 | Asanas stimulate the parasympathetic nervous system (PNS), which is the source of your relaxation response. It is what helps you wind down after a long day at work. It is what slows your body down. It relaxes muscles, lowers your BP, slows your heart rate and breath, starts your digestive juices flowing, and gets your bladder and bowels ready to do their thing. Exercise stimulates the sympathetic nervous system (SNS) which is involved in energy output. When the SNS is activated, we feel it as being stressed or excited.
11 | Regular practise of asanas harmonise endocrine secretions. The endocrine system works through glands which secrete hormones. When this system malfunctions, we get diabetes, hypothyroidism, obesity and goitre.
But it is advisable to first learn yoga with the help of a trained teacher. 
 
Thanks : www.timesofindia.com - 10.Nov.2011
http://www.timeswellness.com/article/45/20111111201111101743094242b4087f2/Yoga-vs-regular-exercise.html