Long-term outlook

In addition to forecasting the weather, Germany's National Meteorological Service (DWD) also evaluates data regarding climatic changes in Germany over the last 130 years.

While the forecasts describe the actual weather, the DWD, as well as other meteorologists and scientists, can use the organization's records of years worth of weather in a particular spot to evaluate climate change over the long-term.

"The year 2010 was not a good one for climate protection," DWD President Gerhard Adrian. "Humans emitted almost 31 billion tons of carbon dioxide. It's a sad record."

Climate change is warming the planet, Adrian said, adding that a cool year in Germany, which makes up only a tiny fraction of the Earth's surface, wouldn't change that.

Noticeable increase

There's been a noticeable increase in average temperature in Germany, according to meteorologist Sven Plöger.

"Over the last 100 years, it's got about 1.1 degrees warmer in Germany," he said.

While 1.1 degrees C (1.98 degrees F) may not sound like much, it's quite radical compared to the gradual change of temperatures that ended the last ice age around 12,000 years ago, Plöger said.

"Compare the value to the overall 4.5 degree increase since the last ice age and it's clear that global warming is happening very fast," he added.

The German weather service pointed to April 2011 as an unseasonably warm and dry month.

"The month was extremely warm, sunny and dry - just like it was two other times in the last five years," DWD climate analyst Gerhard Müller-Westermeier said. "The mean temperature in Germany was an enormous 4.2 degrees above average."

Complex models of reality

Climate change critics have argued that the increase in temperatures may not be related to human activity and claim the earth may have been warmer for a period during the Middle Ages, before industrial carbon dioxide emissions.

However, climate scientists who have reviewed this period, like Phil Jones of the University of East Anglia, contest the assertion of a global 'medieval warm period,' saying proponents appear to be confusing changes in surface temperatures with changes in precipitation.

In Germany, weather is largely dictated by the North Atlantic oscillation (NAO) - a system of fluctuations in pressure between the lows of Iceland and the highs of the Azores.

Winters in Germany are mild when there are large oscillation differences and colder when there is less of a difference between the two pressure systems.

"The question for climate researchers is whether the North Atlantic oscillation difference is low because of climate change or is something else behind it," Plöger said. Looking at historic data, he said the NAO has periodically fluctuated.

Getting people's attention

A noticeable effect of the fluctuations occurred in the dry spring of 2010 that led to meager harvests for German farmers.

The smaller potatoes and more expensive fruits and vegetables received considerably more attention than historic looks at weather data, and emotions ran as high as the temperatures.

Then when large amounts of snow fell in the winter, interest in the effects of global warming and climate change tapered off.

But regardless of what causes the fluctuations, climate researcher Hans von Storch said it's up to politicians to decide how nations react to the long-term trend.

"Do we want more wind energy or not? That's a political question," he said. "We can't be incapacitated by asking science to tell us what we should do."

Author: Kay-Alexander Scholz / sms

Editor: Nathan Witkop