Simulating a Virtual World…For 500 Years!

This work is able to simulate an ecosystem with  up to 500,000 plants for 500 years. Buckle up   Fellow Scholars, because we are going to see  simulations with tipping points, deforestation,   Yosemite valley, and the story of shrubs and  pines. Yes we are in for a ride with this paper. This simulation goes down to the  level of individual branches.    Awesome. And this can simulate cloud  formations too. And it gets better,   it also simulates how the  ecosystem responds to it. Dear Fellow Scholars, this is Two Minute  Papers with Dr. Károly Zsolnai-Fehér. Now, we know that a good simulation paper  has to be able to give us interesting   insights about the world around us.   Does this do that? Well, look. First,   we see clouds everywhere above the  rainforest. Now, unfortunately,   here comes a little deforestation, this is just  a simulation, no real trees were harmed at all,   and look, the clouds disappeared! And, when the  forest slowly grows back, see? The clouds come   back too. Why is that? Because of transpiration.   This means that rainforests release water vapor   into the atmosphere. The trees sweat, if  you will. Now, this vapor rises, cools,   and condenses into clouds. As we have deforested  this region, we have disrupted this beautiful   dance, and thus, no more clouds. And this paper  can simulate all of these phenomena. Love it. Now, let’s have a more drastic experiment.   Here you see how this virtual ecosystem   reacts to decreasing precipitation.   In other words, what would happen if   there would be less and less rain. Things  are going as we expect them to go - new,   different kinds of species arise that  can thrive in this kind of climate…and   wait what? Uh oh… what is happening? Well, Fellow  Scholars, this is the effect of the tipping point,   this means that the effect of some changes is  predictable up until a point, and after that,   unpredictable, and often catastrophic changes  happen. And these are often irreversible. Now a slow drought commences, and look  at the patterns in which this shrub land   slowly recedes. Why slowly? Because  they are really good at adapting to   the new conditions…until a  point, of course. However,   when we do the same thing faster, rain is gone  quicker, the patterns are suddenly clumpier. And if we do the slow drought simulation with  pine trees, you remember from a previous episode   how they grow their roots, now these are not so  good at adapting to the new conditions, so even   in the case of the slow drought, let’s see… yes,  they disappear in clumps. Oof. Now I know what you   are looking for, how can the pine trees deal with  a fast drought. Unfortunately, they do even worse. And now, hold on to your papers Fellow Scholars,  because now we are going to do both and see what   happens. Add shrubs and pine trees at the same  time. This is a simulation after all. We can   do whatever we want here. And…look at that!   The two species cooperate and compete at the   same time, forming these beautiful striped  patterns that would not appear otherwise. So, in such a simulation paper, we always ask,  this sure looks nice, but is this all for show,   or is this what would really happen in reality?   Well, look at this. Here are the patterns that   emerge in theoretical results in these cases,  and here is the simulation. Wow. Feast your   eyes upon this incredible agreement. And  it gets even better. When leaving theory   behind, and comparing to real photos in  real-world places, wow. I am out of words. And we have two more experiments. First  is simulating how microclimates emerge.    This is a multi-species simulation where we get  species taking place right at the center of the   formation. These folks love a wet climate.   But not everyone does. These species like a   dryer weather. Let’s remove both of them.   This corridor then regrows these species,

showcasing the famous forest edge effect  where different species carve out their   niches, responding to the subtle  changes in light and moisture. And now, if you allow me to, I could not  resist this one. In the shadow of Yosemite's   majestic Half Dome, a thick forest of  pines whispers of nature's intricate   dance. As we toy with the vapor in the air,  mimicking the breath of a changing climate,   the trees form curious ribbon-like  patterns across the terrain. But   suspense hangs in the air; this lush tableau  is on borrowed time as the forest withers,   leaving behind a haunting, arid landscape with  only the hardiest of trees clinging to life. This is a beautiful, utterly fantastic  paper with lots of gorgeous results.    Make sure to have a look at the paper  in the video description, and if you do,   you are not only fulfilling your Holy Duty  as a good Fellow Scholar, but you’ll get to   know more about how to simulate the classic  water cycle, how transpiration takes place,   how trees sweat if you will, vegetation modeling,  soil modeling, weather modeling, you name it. And now, you know what’s coming. This  is coming. This is a magical paper,   and only about 400 Fellow Scholars seem to have  read it before this video. And this is why Two   Minute Papers exists, to give a voice to these  researchers and show to the world how amazing   these papers are. That is my quest. And thank  you so much for coming with me. I absolutely   love my job doing this. If you enjoy this too,  consider subscribing and hitting the bell icon.