Earth Science / Science

The myth of global warming?

“Why do people say that there is global warming when it gets colder here every year?”

Screenshot of weather statistics for Yorkshire

Let’s start by just looking at the world the way it is, right now, without worrying about climate change. Everywhere has its local typical weather, right? Like where I grew up in Yorkshire, the prevailing weather is wet and windy. In summer it’s warm and wet and windy, and in winter it’s cold and wet and windy. There’s some days in between where we see the sun, but I bet if you looked at the whole year round, it’d rain more days than not. It certainly feels that way!

But the weather in Yorkshire doesn’t just sit above Yorkshire unmoving. Instead, it’s a result of general trends. Clouds form when warm moisture-bearing air meets colder air, and the water condenses — just like water condenses on a cold mirror in the bathroom after a hot shower. Warm moisture-bearing air comes from the tropics, where it’s warm enough for water to evaporate, and it changes the weather wherever it goes. There are also warm currents in the sea, which warm the air above them. Altogether, this means local weather can be quite mild even quite far north, if the prevailing winds tend to be warm and there’s a current of warm water near the coast.

Now back to climate change. For various reasons, scientists think that the Earth is heating up. Our protective ozone layer is letting in more heat from the sun, while our melting icecaps are reflecting back less of the sun’s heat into space. The more they melt, the less they can reflect the sun’s light, and the more heat is absorbed into Earth’s atmosphere. While this is generally causing the Earth to warm up, the systems I described before mean that it doesn’t have the same effect everywhere. For example, those melting icecaps are releasing near-freezing water into the seas! That means things are changing, and places which used to enjoy warm local weather are no longer protected by warm currents of air and water, as the paths of those currents change.

So even though Earth as a whole is getting warmer, a particular locale might be getting colder. That doesn’t mean they’re unaffected by climate change — quite the opposite. You can expect changes like that to continue and perhaps get more extreme if the climate continues to change. If your local area is staying more or less the same, that’s a lucky chance and that’s all. It probably won’t last.

2 thoughts on “The myth of global warming?

  1. Thank you for the nice blog! You shared some nice ideas here!

    I also think it’s often that we estimate local trends wrong. Some month I thought it rained all the time, but when I check my local weather statistics, it was below average. The same would be true for temperatures, at least for me. But that’s what statistics are for. For example NASA has a nice video [here]( where you can see where in the world it warmed or cooled since 1884 (in comparison to 1951-1980, so the beginning is all cold). At least on that scale there are not many cold places left. But of course, as you wrote above, small scales change a lot and you local micro-climate may be completly different due to e.g. mountain ranges changing the abovementioned warm winds and/or water streams.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s