It took evolution 3 or 4 billion years ago To produce Homo sapiens. If the climate had completely failed only once in that time, evolution would have completely stalled and we wouldn’t be here now. In order to understand how we arose on planet Earth, we will need to know how Earth has managed to survive a decent life span of billions of years.

This is not a trivial problem. Current global warming shows us that the climate can change dramatically over the course of a few centuries. Over geological time scales, it is easier to change the climate.

Calculations show that there is a potential for Earth’s climate to degrade to temperatures below freezing or above boiling point in just a few million years.

We also know that the sun has gotten 30 percent brighter since life first evolved. In theory, this should have caused the oceans to boil now, given that it wasn’t Generally Frozen to the ground early – this is known as “Faint youth of the sun paradoxHowever, somehow, the habitability puzzle has been solved.

Scientists came up with two main theories. The first is that Earth could possess something like a thermostat – a feedback mechanism (or mechanisms) that prevent the climate from roaming into deadly temperatures.

The second is that among a large number of planets, some may have succeeded in passing through luck, and Earth is one of them. This second scenario is made more plausible by the discoveries in recent decades of many planets outside our solar system – the so-called Exoplanets.

READ  금성에서 지질 활동의 징후 발견

Astronomical observations of distant stars tell us that many of them have planets orbiting around them, and that some of them are of such size, density and orbital distance that temperatures suitable for life are theoretically possible. It has been estimated that there is at least 2 billion of these are candidate planets In our galaxy alone.

Scientists love to travel to these exoplanets to check if any of them match up to a billion years of climate stability on Earth. But even the closest exoplanets are orbiting the star Proxima Centauri, More than four light years away. It is difficult to obtain observational or empirical evidence.

Instead, I discovered the same question through modeling. Using a computer program designed to simulate the evolution of the climate on planets in general (not just Earth), first 100,000 planets were born, Each has a randomly different set of climate reactions. Climatic reactions are processes that can be enlarged or contracted Climate change Think, for example, about melting Arctic sea ice, which replaces sun-reflecting ice with an open sea that absorbs sunlight, which in turn leads to more warming and more melting.

In order to investigate how likely it is that each of these diverse planets will remain habitable on massive (geological) time scales, I simulated every 100 times. Each time the planet started with different initial temperatures and was subjected to a randomly different set of climate events.

These events represent climate change factors such as Super volcano Bangs (eg Mount Pinatubo But much bigger) and asteroid Effects (like the one that killed Dinosaurs). In each round of the 100 cycles, the planet’s temperature was tracked until it became very hot or very cold or survived for 3 billion years, at which point it was seen as a potential melting pot of intelligent life.

READ  SpaceX 위성의 의도하지 않은 전자기 방출

The simulation results give a definite answer to the housing problem, at least in terms of the importance of feedback and luck. It was so rare (in fact, only once out of 100,000) that a planet had such such strong stability feedback that it remained habitable 100 times, regardless of random weather events.

In fact, most planets that have remained habitable at least once, have done so less than ten times out of 100. On nearly every occasion in a simulation when a planet has been habitable for 3 billion years, luck was partly due to luck.

Randomly generated 1000 different planets and play twice. The green circles show habitability for 3 billion years. (Toby Terrell)

At the same time, luck in itself turned out to be insufficient. Planets specially designed to have absolutely no reflexes, never remained habitable; The random walk, which is prone to weather events, the path never lasted.

This overall score, results partly based on feedback and partly on luck, is strong. All sorts of changes to the modeling did not affect her. By implicitly, the Earth must thus have some reactions to stabilizing the climate but at the same time Good fortune It must also have participated in its remaining habitable.

For example, if an asteroid or solar flare was a little larger than it was, or it happened at a slightly different (more important) time, we probably wouldn’t be here on Earth today.

It gives a different view of why we are able to revisit Earth’s so gorgeous and expansive history that is evolving, diversifying, and becoming more and more complex to the point that it gave rise to us. Conversation

READ  알래스카, COVID-19 사망자 5명 추가 보고, 입원 계속

Toby Terrell, Professor of Earth System Sciences, University of Southampton.

This article was republished from Conversation Under a Creative Commons license. Read the The original article.

답글 남기기

이메일 주소는 공개되지 않습니다. 필수 필드는 *로 표시됩니다

You May Also Like

NASA의 웹과 허블이 결합하여 우주의 가장 다채로운 모습을 만듭니다.

MACS0416 은하단의 전색상 사진은 NASA의 제임스 웹 우주 망원경의 적외선 관측과 NASA의…

왜 일부 개구리에는 이빨이 있습니까?

개구리의 입 안을 자세히 들여다 볼 이유가 없었을 수도 있지만, 그렇게했다면 입천장과…

Perseverance Rover는 화성을 비행하는 헬리콥터의 놀라운 비디오를 캡처합니다.

재치 헬리콥터 화성에서 비행 2021년 9월 4일.그림: NASA / JPL-Caltech / ASU…

‘평소보다 큼’: 올해의 오존층 구멍은 남극 대륙보다 큽니다 | 오존층

매년 발생하는 오존층의 구멍을 모니터링하는 책임이 있는 과학자들은 그것이 “평소보다 더 크고”…