# Tag Info

Accepted

### What place on Earth is closest to the Sun?

This is an interesting question, but it lacks a key factor that is crucial to the answer: TIME. The point on Earth closest to the Sun varies through time, so the question can be asked about any ...
• 17k

### Does human body temperature impact climate change?

Does human body temperature impact climate change? Directly? It's not even a blip. The Earth's population is 7.6 billion. With each person radiating about 80 watts (basal metabolism), that's about 600 ...
• 20k
Accepted

### Is it true that distance between earth and sun is closer in winter season (January) and farther in summer season in the Northern Hemisphere?

Yes, it's true (in the northern hemisphere). The small eccentricity of the Earth's orbit is not anywhere close to a key driver in the seasons. The key driver of the seasons is the Earth's obliquity. ...
• 20k

### Would life on Earth survive without the Sun?

The answer is No, the Earth would not remain in any recognizable form without the Sun. There would still be a husk of a dead planet with a small amount of energy coming from the residual heat of ...
• 1,891
Accepted

### Changes in Earth's orbital and rotation speeds

The Earth moves faster around the Sun when it is near its perihelion (the closest point of its orbit to the Sun). And it moves slower when it is further away (aphelion), just as Kepler realized quite ...
• 17k

### What place on Earth is closest to the Sun?

It is impossible to know. Solar flares can have more than 500,000 kilometers. So if we consider them part of the sun, the moment when the earth is closer to the sun can be very different from ...
• 109

### Is everything affecting everything on Earth?

Do you know what the weather will be in four hours time? You can probably make a very confident guess. How about this time tomorrow? You can probably make a reasonably confident guess. How about this ...
• 4,060
Accepted

### How to run earth system, land surface and climate models?

As alluded to in some of the comments, all of the CMIP5 models will have been run on supercomputers, and it takes a lot of effort to get one of them running on a new platform, even for a team who know ...
• 3,133

### Would life on Earth survive without the Sun?

The Earth is as it currently is and has been since most of the Phanerozoic (542 Ma), the Eon of life, because of some important (not exhaustive) characteristics presented here, being: its inclination ...
• 2,623

### The free oxygen (O$_2$) in the atmosphere is largely a result of what process?

You are correct in thinking that oxygen comes from photosynthesis. In fact it is so much associated with photosynthesis, as opposed to any inorganic process, that the presence of oxygen in the ...
• 14.1k

### Half of Earth with most landmass

You would have to cut somewhere along this circle: The only landmass here is New Zealand, eastern Australia, eastern PNG, western North America and some Pacific islands. I'm pretty sure you can tweak ...
• 22.2k

### How to run earth system, land surface and climate models?

We are moving all of CESM to open source - in particular here is the latest version of the Community Terrestrial Systems Model (CTSM) https://github.com/ESCOMP/ctsm Formerly known as CLM, CTSM ...

### Is it true that distance between earth and sun is closer in winter season (January) and farther in summer season in the Northern Hemisphere?

David's answer is correct, but I wanted to elaborate a bit further. The Earth's axis is tilted about $23.5^\circ$ from being perpendicular to the plane of its orbit (as David mentioned, 'obliquity' ...
• 163

### Is everything affecting everything on Earth?

The media loves the butterfly effect, but they also love to mis-portray what it means. When Lorenz gave his talk "Predictability: Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in ...
• 20k
Accepted

### Do ocean level rise estimates account for mantle elasticity and plate mass changes?

Sea level rise estimates use changes in relative mean sea level. The definition being: Relative sea level is the sea level related to the level of the continental crust. Relative sea level changes ...
• 14.7k

### Why does Meteorology rely on a spherical model of the earth, rather than a flat earth, to function?

Meteorology relies heavily on a spherical model of the earth. If you consider one of the major "forces," the Coriolis force, it is derivable only from a spherical earth. Now, there are ...
• 8,307
Accepted

### What is the life-cycle of agricultural water used to grow crops/animals?

The linked article talks about irrigated agriculture so I'll focus on that, but things are generally the same for rain-fed agriculture, except you have less control on the water application and there ...
• 4,309

### What is the life-cycle of agricultural water used to grow crops/animals?

The water cycle isn't geology, but it's important to pedology, which is an earth science. Agricultural water can be converted (by photosynthesis) directly into simple carbohydrates that we eat; or ...
• 531

### Would life on Earth survive without the Sun?

Popular science has a good write up on this. In short, everything on the surface is doomed in a year or two. Life in the Oceans would last several hundred thousand years. After that, it's probably ...
• 303

### Why doesn't the earth become superheated?

A body has to emit as much thermal energy as it absobs to remain in thermal equilibrium. The Earth has been doing the same since its formation, i.e, it absorbs solar shorwave radiation by its ...
Accepted

### How was the Earth formed?

The following quote from Birth of the Earth explains the current theory/model for the formation of the Solar System: Long, long ago (some 5 billion years ago) in a perfectly ordinary place in the ...
• 20.3k

### Differences between hydrothermal vents on Earth and Europa

At the moment, the question is unanswerable, because nobody knows if the vents exist - or even if there is an ocean under Europa's icy exterior (although the idea is reasonably well-accepted). At the ...
• 898

### What place on Earth is closest to the Sun?

The point on the surface of the Earth where the Sun is currently immediately overhead is called the Zenith Point. Its Latitude and Longitude correspond to the Declination and Greenwich Hour Angle of ...

### Luis Alvarez's K-T Impactor Calculation

The volume of a sphere is $\small\sf{\frac4 3\pi R^3}$, where $\small\sf{R}$ is the radius. The volume of Earth with the 4 cm deep iridium rich layer is, \$\small\sf{V_{Ei} = \frac 4 3\pi (6.378\...
• 20.3k
Accepted

### How much energy released by the Theia-Gaia impact?

Here's a quick-and-dirty estimate. The gravitational self-energy of a uniform-density sphere is $$U = \frac35 \frac{GM^2}R$$ Let's assume Theia had the same mass and density as Mars, and that Gaia ...
• 431

### What are the criteria that make a planet (in)habitable?

Circumstellar habitable zone There are a few pages that explain the concept in detail, but the gist is that the circumstellar habitable zone is (my definition) The region around a star inside ...
• 898

### Reason for rotting smell after first rain of the season?

When rain displaces pore gasses in the soil, bubbles of soil gas are released into the atmosphere. It's impossible to be precise about the composition because it is so variable from place to place. It ...
• 14.1k