Ocean Currents and Climate Change
Although many people check the weather daily, few think of the ocean while doing so. Most people would be surprised to hear that its existence is vital in the maintenance of the world around us. We can thank currents for relatively predictable weather patterns, easy travel, and the existence of some of our favorite animals. Now, as climate change begins to shape not only the physical but also the biological landscape of our world, it is more important than ever to learn about ocean currents and their effects on life.
One of the most famous ocean currents is the Gulf Stream. The term “Gulf Stream” refers to the swift Atlantic Ocean current with its origins in the Gulf of Mexico. The Gulf Stream itself only extends to the tip of Florida, but the term “Gulf Stream” is often used to refer to both the smaller Gulf-to-Florida current as well as its Northern extension, the North Atlantic Drift. This drift extends all the way to Western Europe.
The Gulf Stream was believed to have been first observed in 1513 by Spanish explorer Juan Ponce de Leon. The first documentation of the Gulf Stream is believed to be the following quote from Ponce de Leon’s logs: "A current such that, although they had great wind, they could not proceed forward, but backward and it seems that they were proceeding well; at the end it was known that the current was more powerful than the wind."
Back in the 16th century, sailors could not navigate without paying attention to this strong current; if they tried, they would veer off-course. As the years passed, sailors began to learn the patterns of the current to improve their efficiency while traveling.
The Gulf Stream also defines weather patterns, particularly those of North America’s East Coast and of Western Europe. It distributes heat directed at the Earth’s equator and spreads it northwards, resulting in more moderate temperatures throughout the globe. It brings warm air (caused by the evaporating warm water it also brings) to Europe, resulting in milder winters.
Ocean currents are also necessary to make the migrations of sea creatures, such as the loggerhead turtle, possible. The most difficult part of migration, called “offshore migration,” refers to the distance a turtle must travel to reach the Gulf Stream. Once it reaches this powerful current, it doesn’t have to worry about navigation. Alterations to ocean currents would result in abnormalities to animal migration routes, which could result in a decreased number of offspring, and even the extinction of a species.
Though the ocean’s currents have been instrumental in shaping and aiding the natural world as we know it, they may also be contributory to humanity’s future demise. To understand why, researchers study the behavior of water. One of the main causes of the ocean’s movement is water density. High salinity and cold temperatures cause a current of colder, saltier water to “sink” under water which is relatively warmer and of a lower salinity. In other words, dense things sink and less dense things float; a lot of salt and less movement of water particles makes water more dense, and vice versa.
Ocean water’s inconsistent density has resulted in what is called the Thermohaline Circulation. This circulation begins in the north, where water on the surface becomes saltier because of the formation of sea ice (which expels salt when formed) or through the evaporation of surface water (the salt remains in the surrounding water). The surface water then sinks because it is saltier and therefore denser than the water around it. The water travels southward to locations near the equator where it surfaces, before evaporation again increases the surface water’s salinity and causes it to sink. It joins the Gulf Stream, returns to the north, and the process repeats. This circulation of water is vital in the maintenance of the Earth’s climate.
As Earth’s temperatures continue to rise, as they have been in recent years, glaciers and ice caps melt. This poses a great problem—for the Gulf Stream and therefore for life. Glaciers contain no salt, thus their melting alters levels of salinity, which are necessary to maintain the Thermohaline Circulation and our climate as we know it today.
Ocean currents aren’t visible to us, which makes it all the more difficult to understand the magnitude of their impacts. In today’s rapidly changing natural world, it is important to examine the intricate cycles that grant us our stable climate and see what can be done about preserving them. Though ocean currents may go unseen, they will never go unfelt.
Alena
Staff Writer, Our Science
One of the most famous ocean currents is the Gulf Stream. The term “Gulf Stream” refers to the swift Atlantic Ocean current with its origins in the Gulf of Mexico. The Gulf Stream itself only extends to the tip of Florida, but the term “Gulf Stream” is often used to refer to both the smaller Gulf-to-Florida current as well as its Northern extension, the North Atlantic Drift. This drift extends all the way to Western Europe.
The Gulf Stream was believed to have been first observed in 1513 by Spanish explorer Juan Ponce de Leon. The first documentation of the Gulf Stream is believed to be the following quote from Ponce de Leon’s logs: "A current such that, although they had great wind, they could not proceed forward, but backward and it seems that they were proceeding well; at the end it was known that the current was more powerful than the wind."
Back in the 16th century, sailors could not navigate without paying attention to this strong current; if they tried, they would veer off-course. As the years passed, sailors began to learn the patterns of the current to improve their efficiency while traveling.
The Gulf Stream also defines weather patterns, particularly those of North America’s East Coast and of Western Europe. It distributes heat directed at the Earth’s equator and spreads it northwards, resulting in more moderate temperatures throughout the globe. It brings warm air (caused by the evaporating warm water it also brings) to Europe, resulting in milder winters.
Ocean currents are also necessary to make the migrations of sea creatures, such as the loggerhead turtle, possible. The most difficult part of migration, called “offshore migration,” refers to the distance a turtle must travel to reach the Gulf Stream. Once it reaches this powerful current, it doesn’t have to worry about navigation. Alterations to ocean currents would result in abnormalities to animal migration routes, which could result in a decreased number of offspring, and even the extinction of a species.
Though the ocean’s currents have been instrumental in shaping and aiding the natural world as we know it, they may also be contributory to humanity’s future demise. To understand why, researchers study the behavior of water. One of the main causes of the ocean’s movement is water density. High salinity and cold temperatures cause a current of colder, saltier water to “sink” under water which is relatively warmer and of a lower salinity. In other words, dense things sink and less dense things float; a lot of salt and less movement of water particles makes water more dense, and vice versa.
Ocean water’s inconsistent density has resulted in what is called the Thermohaline Circulation. This circulation begins in the north, where water on the surface becomes saltier because of the formation of sea ice (which expels salt when formed) or through the evaporation of surface water (the salt remains in the surrounding water). The surface water then sinks because it is saltier and therefore denser than the water around it. The water travels southward to locations near the equator where it surfaces, before evaporation again increases the surface water’s salinity and causes it to sink. It joins the Gulf Stream, returns to the north, and the process repeats. This circulation of water is vital in the maintenance of the Earth’s climate.
As Earth’s temperatures continue to rise, as they have been in recent years, glaciers and ice caps melt. This poses a great problem—for the Gulf Stream and therefore for life. Glaciers contain no salt, thus their melting alters levels of salinity, which are necessary to maintain the Thermohaline Circulation and our climate as we know it today.
Ocean currents aren’t visible to us, which makes it all the more difficult to understand the magnitude of their impacts. In today’s rapidly changing natural world, it is important to examine the intricate cycles that grant us our stable climate and see what can be done about preserving them. Though ocean currents may go unseen, they will never go unfelt.
Alena
Staff Writer, Our Science
Comments
Post a Comment