Superfact 136: Ocean currents regulate global climate but are not the cause of the rapid Global Warming we are witnessing. El Niño events can combine with background global warming to temporarily increase global temperatures but is not the cause of the current rapid Global Warming. The cause for the recent rapid global warming is human activities, chiefly our greenhouse gas emissions. This in turn alters ocean currents and intensifies El Niño.
El Niño is a natural phenomenon caused by the weakening or reversal of the trade winds across the tropical Pacific Ocean. El Niño and the corresponding cooling phase, La Niña, is also called the Southern Oscillation (ENSO). ENSO is referred to as climate variability rather than climate change because the variations in climate are on shorter specific time scales, like a cycle. Other climate variability / cycles are the Pacific Decadal Oscillation and the North Atlantic Oscillation.
El Niño temporarily spikes global temperatures and makes the impacts of global warming worse. It is important to understand that natural climate variability and cycles like El Niño are not the cause behind the rapid global warming / climate change that we have witnessed over the last 150 years.
However, human-caused global heating from burning fossil fuels is making El Niño events stronger. Rising global background temperatures make a warmer atmosphere hold more water vapor. When El Niño happens on top of long-term climate change, it supercharges weather events leading to heavier floods, worse droughts, stronger heatwaves, and severe wildfires. Studies show that El Niño events are more than 36% stronger than they were before the industrial era began, with an acceleration in recent decades. This year we are expecting an extra strong El Niño. You can read more about that here and here.
The ocean and ocean currents are affecting climate. The oceans store heat from the sun and ocean currents help distribute the heat and regulate climate. However, even though ocean currents affect the rate of global warming they are not driving it. Global warming of surface air temperature is as mentioned largely due to increases in greenhouse gases, which lead to increased radiative heat fluxes toward Earth’s surface. You can read more here and here.
I have not come across many claims that specifically states that climate variabilities such as El Niño is what is causing the recent rapid global warming. However, I’ve seen many dismissive comments stating that it is just some sort of cycle (the unknown cycle). Comments such as “climate has always changed”, or “it is natural” are based on the mistaken assumption that scientists haven’t investigated natural causes for climate change. Therefore, I consider it a super fact.
What is not Causing the Recent Rapid Global Warming
This is my sixth and last post in the series about natural causes of climate change that we know are not the cause of the current rapid global warming / climate change. The fact that no known natural cause for climate change can explain the current rapid global warming is just one small piece of the evidence. However, it is a piece that people tend to get stuck on a lot. You often hear claims such as “climate has always changed”. “I think it is a natural cause”. To recap, these are the previous posts.
Superfact 122: We know that the current global warming, or if you call it Climate Change, or Climate Disruption, is caused by us primarily because of our burning of fossil fuels. It is not “natural causes”, and it is not orbital cycles, so called Milankovitch cycles. These orbital cycles include changes in orbital eccentricity, axial tilt, and axial precession. We know that Orbital Cycles are not responsible for the current rapid global warming because Orbital Cycles operate on tens of thousands of years or hundreds of thousands of years, not a couple of centuries. We know that Orbital Cycles are not responsible for the current rapid global warming because the effects of Orbital Cycles are slowly cooling Earth, not warming it. The way the warming happens is also wrong for orbital cycles.
Superfact 124: The Sun is not the cause of current global warming. According to data from NASA, solar energy output has shown no net increase since the late 1970s. In addition, the amount of solar energy Earth receives has followed the Sun’s natural 11-year cycle of small ups and downs with no net increase. Over the same period, global temperature has risen significantly. The current warming is driven by human-made greenhouse gases, not changes in the Sun.
Superfact 125: Volcanoes emit about 0.2 to 0.6 billion metric tons of carbon dioxide per year globally. Our burning of fossil fuels and industrial activities release more than 35 billion metric tons annually. Human emissions are roughly 60 to 100 times greater than all global volcanic output combined. Thus, volcanoes are not the cause of the current rapid global warming.
Superfact 128: There are a lot of natural carbon emissions from the soil, rotting plants, animal and human respiration, and oceans, and a small amount from volcanoes. However, carbon is also absorbed by the oceans, and by plants via photosynthesis, etc., and this creates a balance that has existed for many thousands of years. This is called the carbon cycle. Despite the fact that the carbon emissions from our burning of fossil fuels are much smaller than some of the naturally occurring carbon emissions mentioned, they are what is behind the increase of carbon in the atmosphere because they are a new addition that disrupts the carbon cycle.
Superfact 133: Water vapor is responsible for roughly half of Earth’s total greenhouse effect, but unlike carbon dioxide or methane, water vapor condenses and falls as precipitation. Water molecules only stay in the atmosphere for about two weeks. We do not directly control global water vapor levels. When carbon dioxide warms the planet the atmosphere holds more water vapor, which amplifies the initial warming. However, water vapor does not drive global warming. Carbon dioxide emissions and to a lesser degree methane emissions drive global warming. Water vapor just amplifies the effect.
Conclusion
Climate variability, climate oscillations, climate currents affect climate and are important to climate and are affected by global warming, but they are not the cause behind the recent rapid global warming. It is caused by us primarily as a result of our burning of fossil fuels.
Super facts related to global warming
- Global Warming is Happening and is Caused by us
- The Hockey Stick Graph is not Wrong
- Scientists Agree that Global Warming is happening and that we are the Cause
- Climate change worsens wildfires in the US
- Without carbon dioxide the Earth would freeze
- IPCC Did Not Backtrack on Global Warming Being Human Caused
- Orbital Cycles are not the Cause of the current Global Warming
- The Sun is not the Cause of the current Global Warming
- Volcanoes emit a tiny fraction of carbon compared to humans
- Climate change worsens wildfires Globally and human Land-Use Changes Reduces them
- Carbon Cycle Emissions Does Not Cause Global Warming
- The Most Important Greenhouse Gas Does Not Drive Global Warming
