# Tag Info

16

No, greenhouse gases do not absorb infrared radiation from the sun... the Earth is really the source of infrared. The amount of infrared energy from the sun that reaches Earth is insignificant. Visible light from the sun heats the Earth, NOT infrared light. The visible light passes through the atmosphere and is absorbed by the surface of the Earth. Then, ...

14

I answered this question on SustainableLiving.SE. Since no one voted to close this as off-topic, I'll link and summarize my answer here. I'm glad you asked for it by calorie, since answers on that question had found the data by kilogram, which is not a particularly useful measure. The data source for carbon per kilogram is the Meat Eater's Guide from the ...

13

Here is the mass-calculation. We will consider a column of the atmosphere with a footprint of 1m × 1m. This column weighs about 10,000 kg (per square metre). In these days of climate change we will assume the current average CO2 concentration is 400 ppm, yielding a total mass of CO2 in this column of 4 kg. The rain doesn't wash out the entire thickness of ...

13

How is ist possible that Mauna Loa Observatory is the International Reference Observatory for CO2 Global Meassurments I don’t know that it is ‘the International Reference Observatory’. The Mauna Loa record is almost certainly the most-cited decadal-scale CO2 record, but as far as I know the observatory hasn't been accorded any special status: the record is ...

13

The answer is Volcanos. There might be other inorganic processes capable to produce $\text{CO}_2$, but on Earth, the main inorganic source of $\text{CO}_2$ are volcanoes. In some period of Earth's history, there is evidence of large glaciations events, some of them are thought to have been triggered by the lack of $\text{CO}_2$ (like the Snowball Earth and ...

12

As I understand it, greenhouse gases absorb infrared radiation from the sun. That's not correct. The atmosphere is more or less transparent to the incoming solar radiation. About 29% of the incoming solar radiation is reflected back into space (that's the Earth's albedo). The remaining 71% is absorbed. Clouds and the atmosphere are responsible for a bit ...

11

First of all, the amount of carbon cycling trough the Earth's system is irrelevant to the discussion of the changes in atmospheric $\text{CO}_2$ concentration or ocean acidification. In the same way that the volume of water cycled by the filtering system of a swimming pool is irrelevant to the level of the pool. What matters are the net inputs and outputs of ...

10

One reason is that we know exactly where the current increased CO2 comes from. That is, we know from economic data how much petroleum, natural gas, & coal is extracted and burned. From that simple chemistry lets us compute the amount of CO2 produced, and we find that (after allowing for factors such as e.g. some being absorbed by the oceans) that the ...

10

[Major edits below] In short the answer is NO. Before we get into volume changes, I have to say that volume is a tricky measure to apply to the atmosphere as a whole, because there is no clear limit between the atmosphere and outer space. Also, the thickness of the atmosphere is quite insensitive to changes in atmospheric mass. For example, the atmosphere ...

9

The freezing point of carbon dioxide is -78.5C. The temperature at which carbon dioxide sublimates is not a fixed value. It instead is a function of the partial pressure of carbon dioxide. That value of -78.5° C is the temperature at which CO2 sublimates given a partial CO2 pressure of one atmosphere. The temperature needed to have CO2 sublimate given a ...

9

Right. We can make some estimates of the scale of the problem, but they will come with a healthy margin of error. If we assume that wood has a calorific value of 18.5 GJ/t (from the phyllis2 database) The area burned is 18.6 Mha (from Wikipedia here) The standing volume of material is circa 1500 m3/ha (an educated guess based on Eucalyptus values in Forest ...

9

This reminds me of using Bjørn Lomborg's book in statistics, as examples how not to do statistics, his calculations never make any sense or just make unfounded leaps to conclusions. Erik seems to have the same problem he just throws numbers together with no rhyme or reason. Let's just break down his calculation. 1 °C × 0.30 × 0.04 × 1/4 = 0.003 °C. Why are ...

8

The average global warming due to greenhouse gases corresponds to a 33 Kelvin temperature increase. If you remove all greenhouse gases the average global temperature would then decrease 33 Kelvin (from 288K to 255K). You might want to check out: http://www.nasa.gov/topics/earth/features/co2-temperature.html which estimates the CO2 portion of global ...

8

Firstly, Mars is farther away from the sun than Venus or Earth, so it gets less heat from the sun. Secondly, Venus & Earth are volcanically active, whereas Mars is volcanically inert. Thirdly, the atmosphere on Mars is much thinner than those on Venus and Earth. The density of the atmosphere on Venus is approximately $65\ \mathrm{kg/m}^3$, whereas, the ...

8

No, that will not happen. There is just too much oxygen in the atmosphere. Over 20% of our atmosphere is oxygen. Only about 0.04 % of our atmosphere is CO2, so too much CO2 would kill us much sooner than the lack of oxygen. If you reduced the oxygen concentration in the atmosphere from 20.8% to 19.8%, you wouldn't even feel the difference. If you reduced ...

7

Another way of looking at the question: I take 2 standard wheelbarrows of bits of plants from my garden. One wheelbarrow is used to fill the compost bin. The other goes to the bonfire. How much ash do I have from burning compared to how much compost from the compost bin. Any gardener will know that the amount of compost will be much larger than the amount ...

7

From Scripps: [The] latitudinal differences in fluctuation are the result of photosynthetic activity by plants. As plants begin to photosynthesize in the spring and summer, they consume CO2 from the atmosphere and eventually use it as a carbon source for growth and reproduction. This causes the decrease in CO2 levels that begins every year in May. Once ...

7

Is it true that during the time of the dinosaurs, both the oxygen requirements (by all living creatures on the planet) and the CO2 released by volcanoes were higher than the same type of oxygen requirements today and the CO2 pollution created by us and the currently active volcanoes? I'm not quite sure what "Oxygen requirements" means. It seems to ...

7

One of the consequences that I find more fascinating with the increased CO2 problem is the changes that affect specific components of the environment. One example that I like is the effect on poison ivy. Researchers at Duke University (Mohan et al., 2006), as part of their Free-Air CO2 Enrichment (FACE) experiment, reported a large change in poison ivy ...

7

If you increase CO2 concentration and keep all other parameters at there current level, then biomass production should go up. The reason is simply that CO2 is one of the building blocks biomass is made of in photosynthesis. In the real world it's trickier than that of course. Here you have to take into account how natural cycles will be affected by ...

7

There is no such thing as a single "natural" level of $CO_2$: In Earth's history, there have been levels much higher and much lower than currently, and they are all natural. What we should consider instead is what levels of $CO_2$ are compatible with the mild and stable climate that humanity has enjoyed for the last few millennia, or conversely, which ...

6

The magnitude of these seasonal variations differ from location to location. The graph below portrays variations in CO2 levels at Point Barrow Alaska (PTB), La Jolla California (LJO), Mauna Loa Observatory (MLO), Christmas Island (CHR), Samoa (SAM), and the South Pole (SPO) over the last 60 years. Source: Scripps $\text{CO}_2$ Program, Global Stations $\... 6 Short answer:$\rm CO_2$levels would increase by$209,460\rm ppm$by using all the available oxygen. Long answer: The mass of carbon in Earth's crust is$9(10)^{22}\rm gC$(grams of Carbon). The mass of the atmosphere is$5.15(10)^{21}\rm g$. If all the carbon was burned, or otherwise moved to the atmosphere, then the limiting factor would be the$...

6

If CO2 increases are causing the oceans to warm, does that happen mainly by convection, then? It's counter intuitive to me to think about air convection having that much effect on ocean temperatures. Why wouldn't greenhouse gases' soaking up of infrared instead cool the oceans, that would otherwise be warmed by the radiation? In a nutshell, and as ...

6

From Mary, et al., 1996, Figure 1 on the second page shows a nice breakdown of there the Carbon and Nitrogen go when a plant decomposes. Hadas, et al., 2002 has experimental data from plants with C:N ratios from 11:1 to 136:1. In summary, most carbon ends up in microbial biomass or as CO$_2$. If the process is allowed to proceed to infinity, then ...

6

Your comparison to water vapor is a bad one. The amount of water vapor in the atmosphere does increase with atmospheric temperature. This is because more evaporation occurs and can be held as vapor longer, thus offsetting the equilibrium of water vapor. Cold air will cause more water vapor to condense back to liquid. This process of water cycling ...

6

The climate impacts of CO2 are not constrained to the location they are emitted, but rather the whole globe will feel the effects. CO2 is a long-lived molecule that takes 100+ years to convert or deposit. The troposphere, though, only takes months to mix. There are longer times for mixing between the north/south hemispheres, (e.g. over a year), but it is ...

6

We call this the airborne fraction, although as the name suggests, it's normally expressed as a fraction rather than a percentage. Raupach et al (2014) is an (open access) example of it being used in the literature, and in that paper they quote a long-term 1959 to 2012 value of 0.44, so in the same ball-park as your estimate. Similarly, here's an example ...

6

US EPA Some of the carbon goes into the oceans and soil: Wikipedia The cumulative contribution to the atmosphere is the area of the light blue region of this chart. CarbonBrief, Le Quéré, C. et al. (2016)

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