How Long Would An Ice Age Last (And Why)?

Exact Answer: 100 millions years

An ice age is defined as a period when the Earth’s average temperature drops by 10° Celsius. It lasts for at least one hundred thousand years, and during this period, the planet undergoes dramatic climate changes.

This makes the winters colder and causes snow to cover much more ground than usual, making summers shorter since there are fewer hours of sunlight each day that people can use to grow crops or feed themselves. There is a lot of confusion around how long an ice age would last, and this article will clear it up. 

How Long Would An Ice Age Last?

An ice age is one of the great natural disasters most people know little about, while it also plagues our planet every 100 thousand years or so. We are currently in an interglacial period and within an ice age. 

An ice age refers to a long, geologic epoch of Earth history where global temperatures dropped sufficiently to allow humans to migrate from a temperate climate to warmer regions on Earth as glaciers grow and dominate most regions. 

Typically they last for hundreds of millions of years before warming rates cause meltwater discharge that raises sea levels destructively enough, leading to another glacial state.

The natural cooling mechanism for our planet is the variation in solar intensity called solar fridge. The Earth only catches about 70,000 watts of power from the sun, but that power impacts the Earth unevenly.

The yearly average difference between summer and winter temperatures globally is 60 degrees C. This can vary a lot with altitude. Some places on Earth are regularly experiencing temperature variations of 100 degrees Celsius or more over seasonal periods like day versus night in polar regions. 

In general, as we are heading out of an ice age glaciation. It is also important to note that, during the last 800,000 years, the giant glacial sheets have not appeared frequently. The latest one happened only 20,000 years ago, and the temperature will become colder than today. It will change the distribution of incoming solar energy on Earth.

Why Would An Ice Age Last So Long?

The answer to this question lies mostly in the way the ice ages start.

It depends on different triggered events. But many factors contribute to an individual event. This can vary by location, and geography plays a significant role in determining how things may play out or end during an ice age event globally. 

Some of the top priorities when it comes to factors that lead to an “Ice Age” (also known as glaciation) would include: 

1. The Earth must experience a “cool period.” 
2. There need to be large amounts of extensive snow on land and sea 

No one knows what can trigger an ice age, but some speculators have pointed to a combination of jet streams and solar winds that freeze the northern hemisphere. During an ice age, the point at which glaciers adhere to land turns southward (also called the Pole of Inaccessibility). 

The five big ice ages are the: 

1. Cryogenian glaciation 
2. Huronian glaciation 
3. Andean-Saharan glaciation 
4. Late Paleozoic ice age 
5. Quaternary glaciation 

If this happens, temperatures drop enough such that there is no longer enough natural warmth in the environment for newly iced areas to melt. In addition, winds continue inward from outer space and blow vapor away from plants in Antarctica, making it even more difficult for new ice sheets to form. 

During the ice age, many humans lived in a place which is now Mexico for up to 33,000 years ago. This is impressive because enormous ice sheets covered swathes of land inhabited by thousands and millions of people.

Conclusion

Enormous ice ages account for 25 percent of Earth’s past years. Earth has gone under five big ice ages, which is why our planet has polar ice caps. The sun gets weaker because it is further away from Earth. 

In general, life becomes pretty difficult when an ice age happens. Just like other ice ages, the recent ones brought a lot of glacial advances and retreats. One notable thing is that humans did survive two ice ages. Overall, ice sheets grow for 90,000 years and take 10,000 years to collapse at the time of warmer periods on Earth.

References

1. https://www.nature.com/articles/nature17993 
2. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/JD090iD01p02167