Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Politics : Formerly About Advanced Micro Devices -- Ignore unavailable to you. Want to Upgrade?

To: PKRBKR who wrote (932146)	4/26/2016 6:59:28 PM
From: Wharf Rat	Respond to of 1575175

"But you said 15ppm of lead will kill you did you not?" 15 ppb is the EPA limit, but that too. Also, arsenic is limited to 0.01 ppm. "I wonder how much of the atmospheric CO2 is due to just human respiration." Not as much as you'd like. Does Breathing Contribute to CO2 Buildup in the Atmosphere?September 27, 2010 by climatesight I was recently honoured to join Skeptical Science, a comprehensive database of rebuttals to common climate change misconceptions, as an author. Here I am republishing my first article regarding the common myth that breathing out contributes to the buildup of atmospheric carbon dioxide. It is the Intermediate version, and I have also written a very similar Basic version, which includes a diagram by John Cook. Enjoy! The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact. More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below, glucose) in the oxygen that we breathe in to yield carbon dioxide and water, which we exhale as waste products, as well as energy, which is required to maintain our bodily processes and keep us alive. C6H12O6 + 6O2 ? 6CO2 + 6H2O + energycarbohydrates + oxygen ? carbon dixoide + water + energyIt should come as no surprise that, when confronted with the challenge of reducing our carbon emissions from the burning of fossil fuels, some people angrily proclaim, “Why should we bother? Even breathing out creates carbon emissions!” This statement fails to take into account the other half of the carbon cycle. As you also learned in grade school, plants are the opposite to animals in this respect: Through photosynthesis, they take in carbon dioxide and release oxygen, in a chemical equation opposite to the one above. (They also perform some respiration, because they need to eat as well, but it is outweighed by the photosynthesis.) The carbon they collect from the CO2 in the air forms their tissues – roots, stems, leaves, and fruit. These tissues form the base of the food chain, as they are eaten by animals, which are eaten by other animals, and so on. As humans, we are part of this food chain. All the carbon in our body comes either directly or indirectly from plants, which took it out of the air only recently. Therefore, when we breathe out, all the carbon dioxide we exhale has already been accounted for. By performing cellular respiration, we are simply returning to the air the same carbon that was there to begin with. Remember, it’s a carbon cycle, not a straight line – and a good thing, too! climatesight.org

To: PKRBKR who wrote (932146)	4/26/2016 7:08:08 PM
From: bentway	Read Replies (2) \| Respond to of 1575175

>>Maybe we need to be thinning the herd...<< Oh, we DO. That's why abortion should be legal and encouraged! ALL our biggest problems stem from too many humans on the planet. Let's start with Republicans and conservatives HERE, ISIS and other assholes there...

To: PKRBKR who wrote (932146)	4/26/2016 7:35:05 PM
From: combjelly	Read Replies (1) \| Respond to of 1575175

Given a human outputs so much CO2 I wonder how much of the atmospheric CO2 is due to just human respiration. Why not calculate it? According to here en.wikipedia.org tidal volume is about 0.5 liters for an adult at rest. Breaths per minute is about 16. There are about 526,000 minutes in a year. If about 5% of an exhalation is CO2, that means about 25 milliliters of CO2 per breath. CO2 masses about 44 g/mole. One mole of a gas at STP is 22.4 liters. World population in 2013 was 7.125 billion. To put it in perspective, total world production of coal in 2012 was about 8.6 billion tons. Oxygen masses about 16 grams/mole. Carbon masses about 14 grams/mole. So each ton of coal needs about .57 tons of oxygen to burn it to CO2. There is all you need to calculate how much CO2 is put into the atmosphere per year by human respiration. As a bonus, you have the information to calculate how much CO2 from burning coal alone. Granted, the information won't be exact because it assumes all of the humans are adults and are at rest at all times. Bottom line, no need to make wild guesses or depend on web sites of dubious accuracy. You can calculate the figures on your own. Uh, you do know how to use a calculator?