Plants and algae combines CO2 with water using energy. Why can't we do the same to reverse global warming?

We can. We can plant more plants. But we do that in the form of agriculture and forestry on most all arable land now, so we can't increase the rate very much. Not enough to compare to our use of fossil fuels.

There are studies of adding iron and other trace nutrients to sea water. Algae production (and therefore CO2 uptake) increased dramatically. What is not clear is if that would be sustainable - the algae might just decay or get eaten by an animal and go back to CO2 pretty quickly.

I suspect you are asking why can't we do it in a test tube and than then scale it up to a massive scale through the deserts of the world. Our ability to do do the very delicate chemistry involved has come a long way but not as far as a billion years of evolution. In the next 50 years, so combination of a traditional wet chemistry and bio-engineered materials/lifeforms will make it very doable. Whether we have the political will and economic strength to turn Arizona, the Shara and the Gobi into fields of thin, very green, sheets of glass panels remains to be seen. Yes, sugars would be produced so some type of vegetarian "soylent green" could be made.

Yes but only the first steps of development are happening.

In antother topic i was using this exact means to generate oxygen while recycling carbon dioxide in the space shuttle, or future space shuttle(s).

A Self-propelled shuttle is NASA's future goal. No boosters, no liquid nitrogen or LOX. Self propelled with an unlimited power source.

Greenhouses within a spaceship or in an orbital habitat? base on the moon? Weve seen great examples in movies, Etc.. but what is realistic? Trays. Stackable trays or rows of synthetic bio-engineered plant sponge that does the same thing trees do. Take Carbon dioxide and create oxygen. When this material is developed, we may be able to accelerate the process, thus providing a constant supply of fresh oxygen within a shuttle or space station (confined space), while scrubbing the carbon dioxide from the air.

Then self sufficient space ships, freighters, space stations, asteriod bases or orbital habitats can be constructed and maintained without constant resupply of water or air. This MIGHT also work underwater. Of course, we would need to correctly apply a gravity to this material, as well as simulated sunlight.

there is not any information that nukes ought to opposite worldwide warming, nor could we decide on it to. it ought to shrink the guy-made contribution to greenhouse gases - the rest is as much as the Earth. Storing the waste will not at all be a situation contained in the fast term (say the subsequent 50 years) and there are technologies at the instant under progression to shrink the radioactivity to a element similar to the radioactive ore from which we first have been given the gas. however the undeniable fact that we've little or no "practice" contained in the nuclear marketplace, we've not got lots possibility to attempt new technologies to greater advantageous develop nuclear efficiencies. a colourful nuclear marketplace ought to even open the door to the cleanest of renewable skill ingredients: fusion!

Yes, CO2 combines with H2O to produce glucose (C6H12O6). We could simulate some sort of mechanism that takes in air, processes the CO2 into fuel (glucose) and then expels O2. But we would need to devise a solar panel to drive this sort of device. We would also need to install millions of them to be able to simulate plant respiration.

Basically, it would be too expensive and not worthwhile. A better solution is to plant more trees...they are already equipped to handle this sort of respiration. :)

Yes man can and will do it one day .

What he lacks is the mechanism similar to chloroplast/chlorophyll.

When that riddle is solved we will be independent of plants for our food supply.

Because we are animals, not plants or algae.