Final Blog: Limon, Past and Future

There have been some remarkable changes in the continents in the last 100 million years and more changes are coming. These changes are caused by movement through plate tectonics. But these changes are not only limited to geographical changes. A change in continental place also changes weather patterns and ocean currents and overall climates everywhere. Limon, Costa Rica has been greatly effected from this movement. In fact, if these movements hadn't happened, Limon or Costa Rica, or even most of Central America wouldn't even exist.

Before we look at Limon's past and future, let's reacquaint ourselves with modern day.

Found here: http://www.cpgeosystems.com/presentmoll.jpg

Today Limon sits just above the equator at 9 degrees north latitude and about 90 degrees west longitude. Limon experiences a rather warm and wet climate. It is largely unaffected by severe weather but can have problems with flooding in July when the ITCZ passes over.

Climograph for Limon, CR. Found here: Found here: http://www.world-climates.com/city-climate-limon-costa-rica-north-america/ 

This modern climograph shows Limon has very little change in temperature and a steady amount of rainfall year round with rainy seasons from November through January and a spike in July as mentioned.

But what about 100 million years ago? How has the climate and weather patterns changed for Limon?

Well, to begin with, Limon didn't exist 100 million years ago, at least not in its present form. Costa Rica was formed around 50 million years ago as the Cocos plate moved east, slamming into Mexico and attaching small islands of land as it began sub-ducting the Caribbean plate. But Costa Rica did exist, probably as a group of small islands that would have been farther north, about 15-20 degrees north latitude according to the map below. And it would have been much farther east, maybe right at about 60 degrees longitude.

 

Found here: http://www.cpgeosystems.com/120moll.jpg

This means that the overall climate of Limon could have been much different. It would still be warm year round, though some colder temperatures may be seen because of the rise in latitude, however, global temperatures were much warmer 100 million years ago so probably temperatures were the same, if not even hotter than today.

One thing that would not have been different is the amount of rainfall. Today, Limon sees its rainy season from December through January because the increase in polar air masses pushes warm, moist air across the Gulf of Mexico bringing extra moisture. 100 mya the maritime tropical air mass that brings this moisture would have existed, so it's quite possible that Limon would have had the same rainy season.

But one thing that would have changed would be the movement of the ITCZ. While the ITCZ would have still moved across the equator as it does today, it would have done so differently due to the land masses being in different places.

Found here (ITCZ added by me!): http://www.cpgeosystems.com/120moll.jpg

I believe the ITCZ would have traveled much higher into North America than it does today. The reason the ITCZ pulls so far north today is because the Asian land mass is so huge that it creates a different pressure gradient that pulls the low pressure system north as polar air masses shrink in summer 100 mya. However, this would have still put the ITCZ right over Limon in July. So the weather patterns for Limon 100mya would have been pretty similar. It's even possible that hurricane tyoe storms formed in the tiny Atlantic ocean that existed then, but they would still be swept north by the high pressure systems and would most likely have not effected 100 mya Limon. However, it is possible that hurricane type storms formed off the coast of South America as they are today, and with Limon being farther west than the coast of SA, it may have been effected by these storms much more than it is today.

Climograph made by Cyrus Green

This climograph is pretty similar to the one you would find for Limon today, but you will notice the temperatures are a little higher to reflect the higher temperatures during the Cretaceous. the temperature range is still only a 7 degree change from lows to highs, so no drastic changes through the year.

But what will happen to Limon in the future? Let's look 100 my from now and see!

The continents are going to keep moving in the directions they are moving now. Luckily for Costa Rica, it is on the Cocos plate which will continue to move north and somewhat east while sub-ducting the Caribbean plate. Of course any land that it runs into will be conglomerated into Costa Rica, and this will happen when it comes in contact with Cuba and then Florida, creating a much larger land mass than exists today,

Taken from here: http://www.youtube.com/watch?v=pGACbD4zbWs

This will put Limon much farther north at about 30 degrees latitude, though it will still be at about the 90 degree longitude.This is going to drastically change weather patterns for future Limon. First it will be colder simply because of the latitude change. 30 degrees latitude will put it at about the same latitude that North Florida is today (Tallahassee, Fl is at 27.9 / 82.5). North Florida sees a much wider range of temperatures than Limon today, so it makes sense future Limon will have the same wide swings through the seasons.

This change in latitude is also going to drastically change the amount of moisture Limon receives. It will no longer see a wet season in the northern hemisphere winter because the maritime tropical air will be below future Limon. If it even still exists. The closing up of the Gulf of Mexico will mean the maritime tropical air will no longer exist where the Gulf is today but it will exist on the eastern and western coasts of South America. But future Limon will see higher rain fall amounts in summer time when this maritime tropical air moves northward as the polar air shrinks. This means future Limon will most likely see more severe weather. As the continental polar air mass recedes in the springtime, the maritime tropical air usually mixes with it, bringing the chance for super cells and tornadoes that can effect the southern states today.

Something else future Limon will have to worry about is hurricanes. I'm going to guess the mechinism that causes hurricanes to form off the western coast of Africa and South America today will still exists 100 my from now. And future Limon will have to deal with both fronts. Hurricanes could potentially hit from the east, but will most likely hit South America first, so the effects will be limited. On the western side of South America though there is a "new" Gulf of Mexico formed between Mexico and South America. This could become a breeding ground for future hurricanes meaning future Limon will be right in their path.

Future Limon will finally be rid of the ITCZ! My estimations put it south of future Limon in July.

Photo found here (ITCZ added by me): http://www.youtube.com/watch?v=pGACbD4zbWs

So the spike in rain and the lowering of temperatures Limon now sees in July will no longer exist. All in all, future Limon will see a greater range of temps and a much lower moisture level during the winter and a higher moisture level in the summer.

Climograph by Cyrus Green

 There are big changes ahead for Limon. The change in weather patterns means a change in climate. Future Limon will no longer be able to support the vast amounts of plant and animal life its rain forests support today. It's colder temperatures means less species diversity. There will still be plenty of life. Pine trees, oak trees, and dogwoods are just a few that exist at this latitude today. Animals such as deer, mountain lions, racoons and even black bears live in North Florida today, so future Limon could see this type of wildlife as well. If any of it even exists 100 my from now.  There has been a vast change in flora and fauna since 100 mya and no doubt another vast change will be seen 100my from now.