Ocean Temperature is Rising

Our Ocean

Ranelle Ivens


Ranelle’s addiction to SCUBA started in 2004. From a young age she has been fascinated by the ocean and the creatures living within it. Her Ultimate dive dream is to swim with Orcas and to dive the world. Ranelle is a certified PADI Specialty Instructor and spent 3 years in university studying Science and Biology.

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Down here in Costa Rica, this year past year has been a weird one and 2019 seems to be following suit. As divers, we are constantly paying attention to the weather of the ocean. The ocean temperature, the visibility, the types of wildlife and their quantities, waves, tides, and more. After a while, you get to know the patterns and seasons of the ocean. They change just like they do on land, with temperatures and great migrations as well. However this year, things have been increasingly odd, so much that it scares me.

The Ocean in Playas Del Coco

If you’ve ever dived in or lived near the Pacific you will know it to be the bi-polar ocean that can’t make up its mind. The conditions can change drastically from one day to the next, though it always changes within a bracket. For 5 months of the year in Playas del Coco, we expect the water to be cold (62-75°F) and murky (5-25ft of visibility). It has been this way for decades, except for this year. This year, the cold never came and neither did the plankton.

Isn’t this good news?

We are now 2 months into the 5 months cool diving season and our temperatures are 75-82°F and our visibility 20-40ft. I don’t want to complain as I love the tropical conditions but this is not normal. In fact, this is very very dangerous.

Normally, a northern current flows down the West American coast bringing cold nutrient-rich water into Playas del Coco and beyond. This year it has yet to arrive, and the ocean is considerably warmer for it. With the average temperature for the year raising so significantly, many species are at risk, including humans.

The Effect of Consistently Elevated Ocean Temperature

When the ocean temperature rises, it affects the entire planet. The ocean is essentially the thermostat of the earth, and lately, we have been cranking up the heat. According to the United States Environmental Protection Agency, the surface water temperature has risen by approximately 2°F/1°C in the last 100 years. All the excess heat of greenhouse gases has been absorbed by the ocean as it is trying to regulate the global temperature. If it weren’t for the ocean absorbing all this heat, our surface temperature would have risen by 98.5°F/36°C. In other words, we’d all likely be dead or burning to death in a worldwide desert.

Instead, the Ocean has saved our asses once again. And as a result, it is suffering from our benefit. Below is a list of just a few of the effects of a warmer ocean.

  • Mass Coral bleaching and death
  • Oxygen deprivation
  • Increased risk and transmission of water-borne diseases
  • Expanding water is eating up the coasts
  • Loss of coastal habitat for marine mammals such as seabirds and turtles
  • Failed Breeding (species giving birth to a sole gender or, no hatching at all)
  • Reduced fish populations, and reduced catch by Fisheries
  • Ocean acidification (pH imbalance)
  • Changes the flow of major ocean currents
  • Change in major weather systems
  • An increase of the El Nino effect (reduced rain in tropical climates)
  • Extreme droughts and floods
  • Glacial melts
  • Much, much, much more, that you can download and read here. In a detailed publication by more than 20 scientists explaining ocean warming).



This is happening NOW

Not in 10 years from now, but already happening. all of the effects listed above have been observed, they are NOT predictions. I personally have experienced many of these changes. This year in Costa Rica was one of the driest rainy seasons yet, and we have suffered from major drought. The year before changes in the weather system resulted in hurricanes which are almost never seen in this region. We also experienced major flooding the likes of which have never been seen here either.

Now it is once again showing itself in an increase in the number of female turtles. In addition to this, as I mentioned earlier, the northern current that usually hits Playas del Coco has yet to arrive. As a result, the Giant Pacific Mantas Rays that usually visit us this time of year are scarce along with various other species of stingray.


If you haven’t put two and two together already, it’s because humans suck. Both figuratively and literally. We are sucking this planet dry of resources, and life. Soon we will even suck ourselves dry. Our consumption of petroleum, coal and even conventional livestock has resulted in an excess of greenhouse gases.

Since the ’50s, the ocean has absorbed 93% of those gases, while the other 7% has been hurrying along ozone depletion. Unfortunately, we are not doing enough to reduce our emissions even though scientists have been telling us to do so for years. In other words, we are a bunch greedy pig-headed ignorants causing the destruction of our own planet.


There is an alternative, but it’s not planet B

We don’t have to be greedy pig-headed ignorants, we can be super cool, awesome badass humans instead. We just first need to kick our bad habits and take care or planet A. So I have devised a list of stuff you can do to be a super cool, awesome badass individual.

  • Do everything in your power to reduce your power bill! Save money and the planet? Touche!
  • Stop driving everywhere, burn your fat, not your gas!
  • Whitewash your rooves and your streets, black surfaces radiate heat
  • Install solar panels! Yet another way to reduce your power bill, and it’s a form of clean energy.
  • Try to eat less meat, especially beef. Most people eat more than their daily needs
  • Plant a garden! Trees, flowers, food, it all helps by reducing the amount of CO2 in the air
  • Reduce plastic and water pollution sources

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