I'm not a Certified Science Nerd. On the other hand, I've read a lot of data, and I have a good solid understanding of basic physics. I work in a technical profession, and I can do math. So that's the extent of my qualifications. So without further ado, I will now do my darndest to clarify Global Warming for the layperson.
First of all: despite some data that is incomplete, or has had fudge factors added, two things are clear. One is that the levels of carbon dioxide in the atmosphere have been generally and gradually increasing over the last century or so (we can't be absolutely sure of measurements before then, but we can use cues in the environment like drilled ice cores and tree growth rings) and probably for somewhat longer than that. Average global temperatures are rising at a level that approximately corresponds to the rise in carbon dioxide.
Besides that, we have other empirical evidence that the climate is getting warmer overall. Glaciers are retreating. Mountain ice and snowpack levels are declining. The polar ice cap in the Arctic is clearing during large portions of the year. This was not the case in decades past. Other micro-events have affected climate in the short term - for instance, major volcanic eruptions like Mount Pinatubo in the Philippines have caused short-term cooling for a season or more. But the overall trend is towards warmer temperatures.
Now as I write this, I'm seeing snow flurries outside my window. We've had historic snow storms affect the mid-Atlantic states this year. A few weeks ago, we had snow on the ground in 49 out of 50 states. In other words, that means that global warming is false, right? Wrong.
The mistake the deniers make is this: Weather and Climate are two entirely different things. Most people don't seem smart enough to understand it. I occasionally forget it, too. An average increase of 1 degree Celsius isn't a lot. But that increase means more of the Sun's energy is stuck in our atmosphere. And that energy in turn means more water vapor (which also contributes to warming) and as a result rainstorms can be heavier, snow can be heavier, and tropical storms can grow more powerful. They won't always do that, but there's increased potential.
The other risk with global warming is that a lot of the systems on Earth that produce the climate we know are delicate. For instance, the current flow in our oceans depends on differences in temperature and salinity to move warm water around the globe. Europe's generally warm climate (though they are at northern latitudes) are due to the warm water pushed to them via the Gulf Stream. Should enough fresh water disrupt the Gulf Stream as a result of glacial and icecap melt, it is likely that the flow will be disrupted and Europe will have a relatively sudden shift to significantly colder temperatures. This affects weather patterns on a global scale. And it's happened before.
There are other similar risks. A sea level rise triggered by icecap melt can easily inundate coastal cities, costing billions of dollars. More intense storms cause heavy damage when they hit land. Islands can pretty much vanish. All bad things, and all have varying degrees of likelihood.
Now we're a pretty long way into this process. The level of CO2 has been increasing more and more sharply in recent decades. And even if we stopped completely, as a result of processes in place already we'd still have a rise before leveling off. On the other hand, we don't know how much warming is strictly a result of our atmospheric tinkering, and how much is a result of natural processes outside our control like solar cycles. We know we have an impact, but not exactly how much impact we have.
Is there a solution? Not really. I think we need to try and generate less CO2. Use less power. Pollute less. Try and reduce our impact as a species. On the other hand humans need a functioning global economy. We can't shut it down to save the planet - there are costs that are internal and external. I believe we can and must mitigate the damage as much as we can over time despite the fact that reducing pollution costs money, simply because the externalities are so potentially expensive if we don't.
Right-wing jackasses want to laugh at Al Gore every time it snows in DC. Mainly because they aren't smart enough to see outside DC in the first place. Left-wing dolts want us back in an agrarian society singing kumbaya. Not happening, either. What we need is to make things better, do reasonable things, and work on giving our kids a better planet.
Steps you can take that are simple:
- Reduce your home energy use.
- Replace your incandescent light bulbs with CF or LED bulbs.
- If your heating/cooling system is old, replace it with a more modern system that's more efficient.
- Reduce your driving if you can.
- Turn devices off if you don't need them. Use timers as well.
- Buy local food products whenever you can.
- Turn lights off when you're not using them. Turn off the TV when you go to eat dinner.
- Get rid of the extra fridge in the basement (if you have a house you probably have one)
- Insulate your house. Use better windows. Seal leaks.
- Be considerate of your fellow humans.