56 votes

Global warming - why doesn´t mankind collect heat (thermal energy) and turn it into electricity or send it to space?

This is due to thermodynamics, the three laws of which can be summarized as 1) You can't win; 2) You can't even break even; 3) You can't leave the game. The crucial point here is that heat engines don'...
jamesqf's user avatar
  • 1,748
34 votes

While desalinating ocean water, would it be bad if we didn't pump the brine back into the ocean?

What does it take to reduce the salinity? The salinity of sea water is around 35 g/kg. There are around 1,350,000,000 km³ of water, so roughly 1.3x1021 kg of seawater (1 kg/l, which is a bit off for ...
Arsenal's user avatar
  • 441
32 votes
Accepted

Global warming - why doesn´t mankind collect heat (thermal energy) and turn it into electricity or send it to space?

Collecting thermal energy is really hard. As others have said, things like heat pumps exist for moving heat around, but the laws of thermodynamics (which are fairly fundemantal in physics) require ...
Semidiurnal Simon's user avatar
19 votes
Accepted

How bad is geo-engineering?

The bad part about geo-engineering are the unknown unknowns. Our climate models are wrong. All models are wrong, but some are useful.. Our models are useful, but not quite useful enough to trust ...
gerrit's user avatar
  • 11.6k
19 votes

While desalinating ocean water, would it be bad if we didn't pump the brine back into the ocean?

The residue dry powder you refer to is salt. Salt is toxic to most plants. The United Nations claims the world is already losing 2000 hectares per day of farm land to salt-induced degradation. This is ...
Fred's user avatar
  • 24.6k
15 votes

What would be the effect of bringing seawater pipes to the Sahara desert?

This is an interesting question & I've been waiting to see what answers, if any, would be written. One affect of creating such a lake would be a localized increase in humidity in the vicinity of ...
Fred's user avatar
  • 24.6k
11 votes

Global warming - why doesn´t mankind collect heat (thermal energy) and turn it into electricity or send it to space?

Like passive radiative cooling? The new materials reflect a broad spectrum of light, in much the same way as mirrors or white paint do. In the crucial 8–13-µm part of the infrared spectrum, however,...
Rupert Morrish's user avatar
10 votes

Are there anti-greenhouse gases?

Fundamentally your reasoning is flawed because the major composition of the atmosphere is nitrogen and oxygen. "Pumping a few parts-per-million" of some other gas into the atmosphere won't do ...
f.thorpe's user avatar
  • 13.5k
9 votes

What would be the effect of bringing seawater pipes to the Sahara desert?

Nevada is 286,367 km² in area. With a conservative average evaporation of 2500 mm/yr in your desert, a lake of that size would evaporate 22686 m3/s. That is a flow larger than the average river ...
DrGC's user avatar
  • 1,723
9 votes
Accepted

Would adding sulfur dioxide to the atmosphere have a global cooling effect?

There have been a range of studies on the issue published in Atmospheric Chemistry and Physics and other scientific journals. The short answer is "yes." The longer answer is "yes, but...." In ...
jeffronicus's user avatar
  • 3,474
9 votes
Accepted

While desalinating ocean water, would it be bad if we didn't pump the brine back into the ocean?

The oceans are salty because the slightly acidic rainwater dissolves minerals from ores and rocks and runs into the sea. This is a continual process, a consequence of erosion. However, the salinity of ...
Nullius in Verba's user avatar
9 votes

Why can't we increase cloud coverage of the Earth to reduce mean temperature by flooding basins to increase evaporation?

Barring the technical feasibility of what you are proposing, there's a few points to consider which make your proposal problematic. Water vapor is a greenhouse gas. If you increase evaporation, you ...
f.thorpe's user avatar
  • 13.5k
9 votes
Accepted

Would covering part of Lake Mead with large sheets of bubble wrap reduce the amount of water lost to evaporation?

Something similar has been done with plastic balls. I'd guess they're much easier to manufacture, since it doesn't have to be a continuous sheet. It sounds like there is some local water savings, ...
damp_civil's user avatar
8 votes
Accepted

Were there any plans or proposals for "unilateral geoengineering deployments" before this paper was publsihed?

I think the introduction of the paper itself covers this adequately: … a growing number of studies have investigated regional SG application scenarios, which could prove preferential to a global ...
Pont's user avatar
  • 5,431
8 votes

How bad is geo-engineering?

Seconding eveything that @gerrit mentioned. Additionally, another major problem with geo-engineering is that once we've started these processes and essentially borrowed time to offset mitigation ...
Trevor J. Smith's user avatar
8 votes

What would be the effect of bringing seawater pipes to the Sahara desert?

I see three issues to be considered and will address them in what I think is reverse order of importance: 3) Cost: you have considered this with solar power and by trying to use mud to reduce ...
haresfur's user avatar
  • 4,429
8 votes

Can Ozone (O$_3$) form in a vacuum and if so can it deflect solar radiation

If this would work, would $O_3$ free-floating in very loose clouds in space help deflect solar radiation at all? No, for many reasons: Your cloud will disperse. That's what gases do in vacuum. And ...
David Hammen's user avatar
  • 23.1k
7 votes
Accepted

Are there anti-greenhouse gases?

First things first, the value of 100 for the greenhousivity of standard air is an average for a mixture of gases, this necessarily implies the existence of gases with a value less than 100. ...
userLTK's user avatar
  • 5,847
7 votes

Could a "sunbrella" parked at L1 block enough solar energy to counter global warming?

There are several journal articles on this topic, for example Optimal Sunshade Configurations for Space-Based Geoengineering near the Sun-Earth L1 Point. Being truly at the L1 point is unsuitable ...
DavePhD's user avatar
  • 5,962
6 votes

Is it possible to create clouds by pumping water into volcanoes?

Is it possible to create clouds by pumping water into volcanoes? Maybe, but it's a really bad idea. Here's why: Volcanoes are unexpected and change with time. You can waste two years building a ...
Gimelist's user avatar
  • 23.1k
6 votes
Accepted

How much energy would be required to actively reduce the temperature of the oceans of Earth by 1℃?

The question is slightly confused, because reducing the temperature of the oceans, in a direct sense, doesn't require energy - it releases it. The amount that is released is simply related to the mass ...
Semidiurnal Simon's user avatar
6 votes

Global warming - why doesn´t mankind collect heat (thermal energy) and turn it into electricity or send it to space?

As others have pointed out, if you use the energy, it turns right back into heat. Radiating it back to space is at least theoretically possible. But there is a problem with scale. The Earth ...
Stig Hemmer's user avatar
6 votes

Can Ozone (O$_3$) form in a vacuum and if so can it deflect solar radiation

How exactly are you planning to mine the lunar regolith for oxygen? The oxygen is chemically bonded to metallic cations and it is very energy intensive to extract as molecular oxygen. You might as ...
Gimelist's user avatar
  • 23.1k
6 votes
Accepted

Can we beam heat into space?

If we were to feed this big beam with electricity, would this contribute to reducing the heat on earth? No. The Earth's energy imbalance is estimated to be 0.77 watts per square meter. Multiplied by ...
David Hammen's user avatar
  • 23.1k
5 votes

How Can Smog in Metropolitan Cities like Delhi & Beijing Be Reduced?

The first thing to do is to stop putting pollution in the air, particularly very small particulate matter that are produced by combustion. For the Beijing Olympic Games of 2008, the Chinese ...
Fred's user avatar
  • 24.6k
5 votes
Accepted

Could we cool the ocean by reflecting away sunlight to influence hurricanes?

Water has a large thermal capacity. which is why the temperature change between seasons is gradual rather than sudden, especially near the oceans. For water to lose heat time is required. By ...
Fred's user avatar
  • 24.6k
5 votes

In the oil field, when a vertical cylinder coring sample is taken, how is the core severed at the bottom and removed from the formation?

Coring is an important method to get detailed information about the formations, however, it's very time-consuming and costive, so it's only applied when geologists and reservoir engineers need high-...
user2821's user avatar
  • 5,936
5 votes

Wouldn't 'fertilizing' the ocean to increase cyanobacteria, algae and other phytoplankton populations actually INCREASE CO2 levels in the air?

The arrival of plants can only reduce the total CO2 levels because they metabolize carbon and oxygen. Plants don't make CO2 appear which wasn't there, they only absorb and release ambient CO2. Two ...
bandybabboon's user avatar
  • 1,339
4 votes

Would adding sulfur dioxide to the atmosphere have a global cooling effect?

SO2 is a gas in the atmosphere, which does not cool the atmosphere. However, SO2 oxidizes to H2SO4, which gets involved with aqueous chemistry and often leads to sulfate (SO4). Sulfate is an aerosol ...
f.thorpe's user avatar
  • 13.5k

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