By Bob McDonald, host of the CBC Radio One science program Quirks & Quarks.

Perhaps it's the approach of 2012 and dire predictions of doom that have caused media reports of animal die-offs, magnetic field shifts and floods, making it look like the Earth is preparing for mass destruction.  In fact, the events are not related to each other; we just make them look that way.

It's common practice for news outlets to group similar stories together; so, a downtown fire may be followed by a story of a fire somewhere else.  But that doesn't mean the two events are related.

The recent reports of birds falling out of the sky in Louisiana, Arkansas and Sweden became known as "Aflockalypse," because they happened around the same time, giving the appearance of a global event. Soon, any group of dead birds was making the news, then dead fish began showing up in the Arkansas River, dead crabs in the U.K. and tilapia in Viet Nam. Something must be going on, or so it seemed. But such is the perception of our worldwide media, which can group these events together into one newscast or article.

But in fact, animal die-offs are not uncommon, and are often the result of local events such as unusual weather, pollution, disease or even fireworks. But taken together, they look apocalyptic.

Another event that was loosely tied to the animal deaths was the closing of a runway at Tampa International Airport, due to a shift in the magnetic field of the Earth. Gee, if the Earth's magnetic field can close an airport, could it have disturbed the migration patterns of birds, which are known to use magnetic information to navigate?

That's a reasonable question, but not what was happening in this case. The magnetic poles of the Earth are in constant motion, due to convection currents in the fluid metallic outer core of the Earth. The North Pole, currently at about 81 degrees latitude, is moving northwest towards Russia at about 40 km per year. It even wiggles around in an oval pattern more than 80 km long every day because of activity on the sun that shakes our magnetic field like a water balloon tapped by a finger.

Airport runways have numbers painted on the ends to indicate their alignment with Magnetic North, so pilots know what heading to use on approach. In Tampa, the runway was 18R/36L, which means one end points 180 degrees, the other 360 degrees, which in this case, is exactly north-south. Since those numbers were painted, the pole has shifted by a degree, so the numbers have to be re-painted to read 19R/1L. Again, this happens all the time.

In younger days, I frequented a nightclub near Pearson International Airport in Toronto called "Runway 23," due to its position close to the end of the main east-west runway.  The club is no longer there and the runway now bears the number 24, which shows how long it's been since I was in a nightclub.  

The slow wandering of the Earth's magnetic field, and indeed, the complete reversal of the field periodically (the last one was 780,000 years ago), has been going on for hundreds of millions of years, but is so gradual the birds are still able to navigate. It certainly doesn't happen quickly enough to make birds suddenly fall out of the sky in one day. But by stringing together the concept of airplanes, birds and magnetic navigation, the connection might seem to be there. It's all in how you look at it.  If you're looking for the apocalypse, you'll see it.

Strangely, when scientists make connections between worldwide events, such as melting polar caps, warming ocean currents, increasing CO2 levels, tree lines migrating northwards or shifting breeding cycles of fish and birds, then connect them into a picture of global warming, many people have a hard time believing it.

So, why are we so quick to make artificial disasters out of similar but unrelated events, yet reluctant to believe experts who have spent years connecting real and very serious events that add up to climate change?

Perhaps that's a disaster we don't want to see.