CLIMATE SCIENCE: THE FACTS

The information in our climate science video may sound scary, but it’s all based on fully reviewed and reputable scientific research. All the facts in the video are referenced here with a quick explanation.

 

Why we’re heating up

Our story begins in 1896 when Nobel-prize winner Svante Arrhenius discovered that carbon dioxide in the Earth’s atmosphere traps the sun’s rays and keeps the planet warm. Get the facts

The French mathematician Joseph Fourier first realised in the 1820s that there must be something in the air that prevented the Sun’s heat from just bouncing off the Earth and vanishing back into space. In the 1860s, the Irish-born physicist John Tyndall found that carbon dioxide could trap heat, and then in 1896 the Swedish Nobel Prize winner Svante Arrhenius built on this work and linked carbon dioxide in the air to changes in global temperature. His original paper can be seen online here

So having some CO2 is great, because without it the earth would be a frozen lump of empty rock, the problem is that as CO2 increases the planet gets hotter. And ever since the industrial revolution we have been burning more oil, coal and gas, causing the amount of CO2 in the atmosphere, which is measured in parts per million, to shoot up from 290 back in the 18th Century to almost 400 today. Get the facts

The Carbon Dioxide Information Analysis Center has estimates for how much has been burned by different countries since 1751.

We know how much CO2 was in the atmosphere back in the 18th Century then by examining bubbles of air trapped in ice from the period. More information.

Since 1958, a measurement station in Hawaii has been directly tracking the amount of CO2 in the atmosphere.

So according to the science we should be getting hotter. And we are. Over 7000 measurement stations around the world show that the Earth’s surface temperature has increased by one degree Celsius since 1880. Get the facts

These stations are spread over land and sea, and are backed up by temperature measurements from satellites. More information.

Keep in mind the last ice age, as in woolly mammoths hanging out in Europe ice age, was only five degrees colder than today. Get the facts


NASA has said “A five-degree drop was enough to bury a large part of North America under a towering mass of ice 20,000 years ago. More information.

Current Impacts of Climate Change

The words Global Warming may bring to mind a warm lavender scented bath, but the idea that things are just getting warmer is way too simple.

Our planet is a beautiful, interconnected system with huge circulating ocean currents and weather patterns that create the mostly comfortable climate that allows us to grow food and have enough drinking water. Get the facts

Watch this video for a good explanation of this.

But global warming is pumping loads of extra energy into the system in the form of heat and that’s messing with these weather patterns and causing unseasonably hot or cold weather. Like the frozen spring in 2013 that caused serious problems for farmers here in the UK or the droughts that caused major crop failures in the US and Russia in 2012. Get the facts

The warming of the Arctic is believed to be disrupting the jet stream, which is a kind of river of air that wiggles across the Northern hemisphere. It’s powered by the temperature difference between the Arctic and the tropics. As the Arctic warms up, this temperature difference decreases and so the jet stream slows down and starts to form large North-South loops. This can bring long periods of unseasonal weather – either hot or cold – such as the droughts in the US and the frozen Spring in the UK in 2013. So global warming could in fact lead to longer, colder winters in Northern Europe – and this is just one relatively mild example. If climate change starts disrupting the ocean currents that move heat and vital nutrients around the globe then we’re in REALLY serious trouble. See this article for more information.

This article on the Frozen spring explains further and has links to relevant research papers: Scientists link frozen spring to dramatic Arctic sea ice loss



More energy in the system from global warming means more floods, storms, and droughts.

Get the facts


For more information how these different effects are driven by climate change, see the “Frequently Asked Questions” section of the IPCC’s Fourth Assessment Report.

The number of natural disasters per year has more than doubled since 1980, and that’s according to those radical environmentalists the big insurance companies. Get the facts

Insurance companies keep track of natural disasters because it’s in their interest to understand how the risks of major floods, droughts and storms are increasing. Their data shows that while disasters that are unconnected to climate change, like volcanoes and earthquakes, have stayed at roughly the same level since 1980 while climate-related catastrophes have risen sharply.

You can see some of the data that the insurnace industry uses by registering (for free) and accessing the Münchener Rückversicherungs-Gesellschaft, Geo Risks Research.

Future Impacts of Climate Change

Freshwater

More than a billion people rely on water supplies fed by mountain glaciers. If we don’t slow down global warming then these glaciers will rapidly shrink, threatening the freshwater supplies of tens of millions of people in places like China, Peru, and the United States. Get the facts

Information about how climate change could affect water resources can be found in the draft of the Fifth IPCC Report on Page 50.


Food

Farmlands require just the right conditions. If we keep on changing the climate that’s going to mean more floods, droughts, rainstorms which could seriously impact on global food production Get the facts


It probably isn’t surprising that rising temperatures increase the risk of droughts, but a warming climate also means more evaporation of water from seas, rivers and soils into the atmosphere. More water in the atmosphere means more frequent and more severe rainstorms and snowstorms.

Meanwhile, higher average temperatures at the surface of the ocean mean there’s more energy in the water, which increases the strength of cyclones and hurricanes which emerge from the ocean. As if that wasn’t enough, as water heats up it expands, causing sea levels to rise. This rise could be made even greater if large amounts of ice melt from frozen land masses like Greenland and run into the oceans. Higher sea levels make coastal areas more vulnerable to storms, and may lead to land being lost permanently under the ocean.

There is a lot more information on the possible future impacts of climate change in the rather dense IPCC chapter on “Chapter 12: Long-term Climate Change: Projections, Commitments and Irreversibility”

Add to this a growing world population, and you’ve got a recipe for serious destabilisation or even war, as people and countries fight to secure food. Get the facts

See this Human Impact Report for more on the humanitarian impacts of climate change

Tipping Points

And then there are “tipping points” that could shove us into runaway climate change. Just one example is that global warming could dry out the rainforests increasing the risk of major fires which would release more CO2, and so speed the process even further. Get the facts

We chose this tipping point because it’s one of the easier ones to understand, although the level of risk is still hotly debated and varies greatly between forests – see for example Sensitivity of tropical carbon to climate change constrained by carbon dioxide variability and Rapid warming accelerates tree growth decline in semi-arid forests of Inner Asia

There are a number of these tipping points and if we hit enough of them then climate change could spin entirely out of our control. Get the facts

Other tipping points include the complete loss of the Arctic sea ice, which would reduce the reflectivity of the Arctic and lead to more heat being absorbed by the sea ( more information); and the risk of methane, a powerful greenhouse gas, being released from frozen soils by global warming more information.

These are all just predictions, we can’t know the precise details of what will happen as the climate changes. However we also can’t know the precise details of what would happen if we released 200 angry gibbons into an air traffic control tower. But we do know enough to know that it’s probably not a good idea. To avoid those dangerous tipping points we need to get the amount of CO2 in the atmosphere down from 400 to 350 parts per million. This will require some serious changes in our societies, but it is still possible if we just get on with it. Get the facts

This figure has been endorsed by leading climate scientists such as James Hansen and Rajendra Pachauri, and there’s a nice explanation of it here.

 
 
 

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