let play this out, there is roughly 550 billion tons of biomass on earth, assuming roughly 15 MJ/kg of energy stored in that biomass and running E=m*c^2 in reverse (m=E/c^2) this means all the biology of earth stores 92 tons worth of energy, or about the weight of 1 and a half Abram M1 battletanks, or compared to the mass of the earth (5.9742×10^24) kg, undetectably nothing! Because our biosphere is constantly leaking off this energy as entropy its not being gained and is merely holding even and oscillating with every mass extinction and new era. Compare that with the ~1000 tons of space dust that falls on the earth every year and legitimately adds mass be it still smack nothing compare to the total mass of the earth. No, because earf is not something that exists.
So... sinse its leakin off thers no net gain in earfs mass... but new mass IS added to earf dew to sunlight on plants.!!!
Maybe "history" is not the right word. Since the formation of Earth until today and if we consider an equally long period in the future the Earth cools or heats? The Earth loss energy or gain energy? What is the general evolution of the Earth in terms of energy?
Small amounts of mass are added to the planet every day due to particles in space. It would take an enormous amount of light to even register a tiny difference from year to year. The earth itself radiates which only aids in confusion, but it is safe to assume since the earth's mass is getting slightly larger that it is also gaining energy.
Yes, but its not added mass, look just a black rock "gains mass" when light hits it, so this subject of do plants add mass from capture sunlight is moot, anything technically gains mass when it absorbs energy, its just the mass it gains is soo astronomically small its not worth considering.
A physicists answer, and one that belongs on the Microsoft helpline at that. First off, we're talking masses on the order of 10[sup]-52[/sup] kg here. The actual number is less than this, but most molecular bonds are on the order of 1eV in energy. We're talking about Glucose here C[sub]6[/sub]H[sub]12[/sub]O[sub]6[/sub] for a total molecular weight of about 180g/mol for a grand weight gain of 24eV, if we're constructing it from individual atoms. In order to get a weight gain of one single kg, we would need to 'create' 1.25x10[sup]26[/sup]kg of Glucose. To put this in perspective, the earth weighs 6x10[sup]24[/sup]kg, or 1% of this number. Now, bear in mind that the actual change in energy that we're talking about in photosynthesis is smaller than this. Now consider this. Plants undergo respiration at night, it's how the grow, they absorb Oxygen, and metabolize sugars just like we do, and not all plants do both to the same degree, it's only a group of plants that absorb more CO[sub]2[/sub] than they release. Finally, consider this small point... Plants die. They decay, and oxidize, and for the most part revert back to carbon dioxide and water - a process helped along by heterotrophs such as yourself. So no, there is no net mass gain caused by photo synthesis.