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The question is rather simple, the answer is more complex. It is to answer why some places are colder than others. Example: North America is colder than Europe at the same latitude.

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  • $\begingroup$ North America isn't always colder than Europe...in 2009, the icelandic low pushed east and the arctic airmass set up permanent shop over europe...reversely, 2009 was one of the mildest winters for North America on record. Why? The ElNino - La Nina cycle (yes, southern pacific) are in large parts responsible. This question is far too vague to be answered in less than a few thousand paragraphs ;) Normally you are right, and it's all a part of the oceans great heat redistribution system. West coast pacific and atlantic are significantly warmer $\endgroup$ – Twelfth Oct 8 '14 at 3:43
  • $\begingroup$ Yea, it's possible but on average, it's colder. The problem we have (a big problem) is that climate changes are making the climates less predictable. ElNino is becoming more frequent too. And it is not impossible that Europe could become colder than America if the melting of the ice is changing the ocean currents like some scientists are predicting. $\endgroup$ – Vincent Oct 8 '14 at 3:53
  • $\begingroup$ Europe (the UK in particular) is heated by currents of warm water coming north from the tropics. $\endgroup$ – Tim B Oct 8 '14 at 8:23
  • $\begingroup$ This feels pretty broad to me, but I don't have any concrete suggestions on how to narrow it. Are we in "whole books about this" territory? $\endgroup$ – Monica Cellio Oct 8 '14 at 17:40
  • $\begingroup$ No, I designed this to be a complement of Tim B series of questions about worldbuilding. $\endgroup$ – Vincent Oct 8 '14 at 17:43
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Different factors influencing the temperature, stating with the general ones

Type of star and distance from the star: there is a question about that with good answers: What kind of star should I use for my world?

orbit: the orbit the the plane t can have an impact on the temperatures. Basically, the close the planet is, the hotter it gets. Some orbit are more elliptic than others. See Mars for an example: https://en.wikipedia.org/wiki/Climate_of_Mars#Seasons

Albedo: is the reflection coefficient of light emitted from the star that is reflected back into space for a given planet. A high albedo means high reflectivity (colder planet), while a low albedo means the light is absorbed and transformed into heat (hotter planet). It is possible the find the average albedo of a planet but it will vary greatly between different regions.

Atmosphere: A thick atmosphere makes a better distribution of the energy received from the star, resulting in a lower temperature range between the equator and the poles. A thick atmosphere can also influence the albedo of the planet.

Greenhouse effect: certain kind of gases in the atmosphere can trap more energy from the star to keep it in the atmosphere. This will increase the planet temperature everywhere. Most common greenhouse gases include: water vapour, carbon dioxide (CO2), methane and Ozone.

Axial tilt: The axial tilt of the planet is the angle of the rotation axis and the orbit of the planet. The axial tilt on Earth is 23,5° (more or less). One factor influencing the temperature is the angle at which the light of the star is reaching the planet. If you increase the axial tilt, it will increase the temperature differences between the seasons and lower these differences if you reduce it.

Latitude: In theory, the hottest place on our planet at the summer solstice is the tropic of cancer. It is the place that receives the most energy from the Sun at that time of the year. It is the hottest when it’s at 90° and gets colder whit a smaller angle. Places located near the equator tend to have a smaller range of temperature throughout the year. The temperature range gets larger as your get closer to the poles. This is a general rule, but the exceptions are many.

Maritime/continental influence: Areas close to a large body of water will have smaller temperature variations. Areas far from the seas will experience larger temperature variations. This is because water takes more time to change temperature than the land. The energy is absorbed by the water and diffused on the surface but also underneath. On land, the top layer is absorbing all the energy. So, it get warmer quickly but also cool off quickly. Areas that are located not too far from the coast but that are under the effect of offshore winds and areas behind mountains are not really affected by the maritime influence.

Oceanic currents: hot currents from the equator will warm up the surrounding areas while cold currents from the poles are likely to lower the temperatures. This is why New England is colder than France. Despite being at the same latitudes, New England is affected by a cold current.

Wind direction: it’s not the biggest factor when it comes to influence the temperate but since the dominant winds are constantly blowing in the same direction, it has an impact on temperature. In Eastern Siberia, during winter, the dominant winds come from the North West. It’s a cold and dry air flow from the Arctic.

Humidity: places that are really humid like most tropical rainforest aren’t the hottest places on Earth. It’s because of the rain they receive and the high humidity. It acts in a similar manner as being close to the sea since it reduces the temperature variation.

Altitude: temperatures get lower as the altitude increase. Lower the temperature by 6.4°C for each kilometre above sea level. This is true as long as you stay in the troposphere.

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  • $\begingroup$ While negligible compared to that list geothermal, nuclear, and pressure heating are also contributing factors. $\endgroup$ – Black Oct 8 '14 at 5:28
  • $\begingroup$ It's sort of already in the distance from star parameter, but you may want to include ellipticity of the orbit as well: in practice, it changes seasons' length and induces an additional hot/cold cycle which, unlike seasons, is planet-wide. See Mars for example. $\endgroup$ – Khaur Oct 8 '14 at 15:14
  • $\begingroup$ Khaur: thanks I added the suggestion. Black, I already tried to find if this is having an impact and it's seems very minor. $\endgroup$ – Vincent Oct 8 '14 at 17:47

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