Milankovitch cycles: Natural causes of climate change

preview_player
Показать описание
Explanation of natural causes of climate change, like Milankovitch cycles, volcanoes and sunspots.

Full text:
The average temperature on Earth has always fluctuated. Millions of years ago, for example, it was on average 8 degrees warmer on Earth. There were also ice ages thousands of years ago and the average temperature on earth was 2 degrees lower.

How did these temperature differences arise?
First, the sun plays a role. When the sun is more active, sunspots can be seen. This can make it a little warmer on Earth, but this only involves a tenth of a degree of heating. The current global warming can therefore not be explained by a change in the activity of the sun.

Volcanoes also play an important role. During a violent eruption, a lot of ash is released into the atmosphere. This ash, if it enters the atmosphere high enough, can remain in the atmosphere for a long time and block the sunlight. For example, the eruption in 1815 of the Indonesian volcano Tambora in 1816 caused the global temperature to drop sharply and 1816 was called the "year without summer."

Although in the short term the volcanoes cause a temperature decrease, volcanoes cause a temperature increase in the long term. Volcanoes emit the greenhouse gas CO2, which causes the temperature to rise. The earth was once a planet full of ice, but due to a lot of volcanic activity, a lot of CO2 was emitted and the temperature on earth slowly increased.

Milankovic's variables are a final natural influence. Milankovic thought that the temperature on earth was influenced by 3 variables related to the position of the earth relative to the sun. In short, the point is that if the northern hemisphere receives less energy from the sun in the summer, the ice on the North Pole will not melt and an ice age may arise.
First, the Earth does not orbit the sun in a circle, but in an ellipse shape, in which the sun is not centered. This is called eccentricity. The point where the Earth is closest to the sun is annually at the beginning of January.

So in July, the Earth is farthest from the Sun. This is summer in the Northern Hemisphere. Because of the distance, the earth receives less energy from the sun, the ice in the Northern Hemisphere melts less quickly.
This could be the beginning of an ice age.
If there is a circular shape, the Earth is closer to the sun at the beginning of July. This gives the Northern Hemisphere more energy, and the ice melts.

This prevents the formation of an ice age. The eccentricity changes approximately every 100,000 years.
The second is obliquity. This is the tilt of the earth's axis relative to the sun. The Earths axis has a tilt of 23.5 degrees, but this changes between 22 and 24.5 degrees. The wider the angle, the more the northern hemisphere turns toward the sun in summer and the more ice melts. The smaller the angle, the less ice melts in summer and the greater the chance of an ice age. The obliquity changes approximately every 41,000 years.
The third is the precession. This is a toll movement around the Earth's axis that changes every 26,000 years. Here the first two effects are amplified or limited depending on the eccentricity and obliquity.

Now that you have learned how natural fluctuations in the climate arise, we can investigate the consequences of climate change for the earth.
Рекомендации по теме
Комментарии
Автор

Solid!
Top KEK production.
Knowledge is power.
Now you know, and knowing is half the battle.
The other half involves you doing something constructive with the knowledge.
Peace be with you.

grugbug
Автор

great video! loved the animations! congrats!

papel
Автор

Remember the thermohaline currents.
1 milankovitch cycles.
2 sunspots.
3 thermohaline circulation.

aaronjennings
Автор

I think changes in the earths' magnetic field can also precipitate localized changes in climate. In recent years, there has been a large shift in the composite magnetic field. Since the magnetic field is responsible for holding the earths' atmosphere intact (due to protection from solar wind effects), has anyone looked at this as a factor?

rusty
Автор

Thank you!!!! You're my savior!!!!

mayteors
Автор

More CO2, more trees. More trees more production of oxygen which will naturally result in the balancing of the O2/CO2 ratio again.

gordondwyer
Автор

Very good but you miss some details when it comes to the suns effects on climate, like the solar winds which changes in relation to the solar cycles. A weaker sun = less solar winds allowing more cosmic rays to enter the planet, there is growing evidence that this effects cloud cover.

madhaze
Автор

Your lecture is really good but we are from Asian part, so it's is difficulty to understand your ancent so please use subtile that's y we can understand in better manner .
Thanks a lot for such wonderful video .
Keep it up .

bluewhale
Автор

Green house gas co2? But the plants and trees need co2..

Hasdac
Автор

The Milankovitch Cycles, Volcanoes. and Sunspots have always been the prevailing reasoning of climate change for myself. I'd appreciate seeing these factors compared to records on Paleoclimatology, the earliest documented observations of Sunspots, and documented global temperature. Be interesting to see if anything corresponds to global famines, cold snaps, and heatwaves outlined in historical text. The video is well presented.

phoenixrising
Автор

Amazing visual representation and explanation!

May I suggest one correction, the precession cycles last 23ka and 19 ka (giving an average of 21.000 years) (Davis and Brewer, 2009) and not 26.000 as pointed in this video.

giannisgkikopoulos
Автор

What are the Exact Angles of the Precession?

TBoneZone
Автор

I would you suggest discussing the effects of perihelion and aphelion times when having a lower or greater eccentricity. The latter allows Earth to experience perihelion times, opposite to the former. I would think twice on when ice ages are more prone to happen. Thanks for the video.

kawamach
Автор

At what point in the cycle timelines, are we currently at? Can you clarify? Thank you

ST-cywe
Автор

It could be also that all other planets in our solar system endure similar Milankovich cycles the exerts orbital & tilt variance of Earth, thus affecting its climates

skanthaadsigns
Автор

It's a simple explanation of the Milankovic Cycles, not a textbook on earth science.

frankmoore
Автор

I still don’t understand how procession affects the weather

shadowdance
Автор

Milankovitch cycles are clearly not the only cause, otherwise the cycles would have a regular pattern. The Younger Dryas glacial period followed the warming after the last stage 12, 000 years ago and lasted 1500 years. It may have started within a period of less than 100 years and we don't know what the trigger was. Some model studies suggested that three cold summers, e.g. following a volcanic event with a lot of ash in the atmosphere, could trigger a return to glacial conditions. A warming climate is preferable to a cooling one!

karhukivi
Автор

For my 10th birthday a volcano erupted. It was May 18, 1980. I had a horrible birthday cake. It was Disney's Cinderella. It's hot today for winter December weather.

Lawna-igxz
Автор

If this was ancient times people wouls assume God is mad at us, but God is cause and effect. It has nothing to do with good or evil it just... is.

Killerwhale