No. There will not be any major change in the Earth's magnetic field for many more THOUSANDS of years. We are approaching the next field reversal epoch, but buy the year 2013 we still have several thousand years to go before the current field drops to zero strength and is then replaced by a field with the opposite polarity relative to the geographic North and South Poles. There are geomagnetic storms that happen, but there have been hundreds of these in the last century and their effects at the Earth's surface are merely annoying and not life threatening.

The figure at the top of the page shows the strength of Earth's magnetic field for the last 800,000 years. The current strength is at the far left at 'zero' on the horizontal axis. You can see that we have just completed a major increase in the field during the last 50,000 years ( 50 kya on the time axis), and it is now declining in strength. The fiend is declining by about 5% per century, so that in a few thousand years we may be near zero - or it may 'bounce' and we could be on another increase again.

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