Northern Hemisphere

The years 1997, 1995 and 1990 were the warmest in the Northern Hemisphere since the days of Christopher Columbus, according to researchers from the University of Massachusetts at Amherst. And the researchers say that they found evidence that rising levels of greenhouse gases are probably responsible. Geoscientist Michael Mann and his colleagues reconstructed annual average temperatures back to the year 1400 and found no year warmer than those three, they report in today's Nature.

Travelers in Alaska, Canada, the northern Plains, parts of the Midwest and much of the West tonight (Thursday) may be treated to a northern lights display more intense than usual because of the powerful solar storm hitting the Earth's surface, according to science and weather reports. The geomagnetic storm reached Earth about 5:45 a.m. EST Thursday. Scientists say the initial storm has been weaker than expected but may intensify later today. Northern lights trackers say tonight could bring a spectacular show to mid- and high latitudes in the Northern Hemisphere.

As the nation's presidential candidates squabble in New Hampshire, two American daredevils and a Russian cosmonaut are set to put hot air and gas to a more productive use as they ready the first-ever attempt to circumnavigate the globe in a balloon.

It's a little hard to remember that Americans once merely tolerated hops. Sierra Nevada was one of the pioneers in teaching us to enjoy the flavor, and a few years ago it produced this hoppy extreme, brewed with the fresh herb, harvested just 24 hours earlier. The effect is a startling burst of hop flavor, almost dank with heady, resinous aroma. It's a seasonal brew, so it will go out of stock, but good news: Sierra Nevada will produce another Harvest Lager (Southern Hemisphere) in about six months.

The north and south poles on Mars look very different from each other, and scientists now think they know why: Circulation patterns in the Red Planet's very thin atmosphere tend to keep all the water in the north, leaving the south pole high and dry. The exploration of Mars by unmanned spacecraft has shown that the northern hemisphere has a large polar cap made up mostly of frozen water while the southern hemisphere has a much smaller cap made up...

If you don't believe in horoscopes, you're in step with science. But that's not the same as saying the season of your birth cannot affect your fate. Hundreds of studies, published in peer-reviewed journals, have suggested that the month a person is born in is associated with characteristics such as temperament, longevity and susceptibility to certain diseases. Scientists say that even though some of these findings are probably spurious - if you dig around in data, you will eventually find correlations just by chance - other effects are very likely real, triggered not by the alignment of the planets but by exposures during prenatal and early postnatal lives.

First, the disclaimer: A few years ago, one of this book's co-authors wrote me asking for research suggestions on the subject of border radio; I lent a hand--actually, more like a finger--and did not see their work until after it was complete. Now, the review. Fifty years ago you probably would have had just one radio in your home, and chances are at night it would have been tuned to one of the border blasters, those megawatt stations that dotted our 2,000-mile frontier with Mexico.

An industrial pollutant responsible for acid rain may be reducing Earth's warming from the "greenhouse effect," especially in the Northern Hemisphere. In research published last week in the journal Nature, a British climate expert said his calculations show the effects of man-made sulfur dioxide are large enough that they "may have offset the temperature changes that have resulted from the greenhouse effect." In his study, T. M. Wigley of England's East Anglia University created a computer model and determined that the pollutant's cloud-forming potential may be capable of reducing the warming impact of other man-made gases.

IT'S NOT JUST NATURE THAT abhors a vacuum; man does too. That sucking sound you hear is the noise made by thousands of young immigrants as they travel from the overpopulated Southern Hemisphere to the more prosperous Northern Hemisphere in pursuit of employment. The phenomenon is putting pressure on economies from Oslo to Okinawa, and it is fueling raucous worldwide debates about immigration and motherhood.

Travelers in Alaska, Canada, the northern Plains, parts of the Midwest and much of the West tonight (Thursday) may be treated to a northern lights display more intense than usual because of the powerful solar storm hitting the Earth's surface, according to science and weather reports. The geomagnetic storm reached Earth about 5:45 a.m. EST Thursday. Scientists say the initial storm has been weaker than expected but may intensify later today. Northern lights trackers say tonight could bring a spectacular show to mid- and high latitudes in the Northern Hemisphere.

If you don't believe in horoscopes, you're in step with science. But that's not the same as saying the season of your birth cannot affect your fate. Hundreds of studies, published in peer-reviewed journals, have suggested that the month a person is born in is associated with characteristics such as temperament, longevity and susceptibility to certain diseases. Scientists say that even though some of these findings are probably spurious - if you dig around in data, you will eventually find correlations just by chance - other effects are very likely real, triggered not by the alignment of the planets but by exposures during prenatal and early postnatal lives.

Tyrannosaurs may have stalked far more of the globe than previously thought. Scientists for the first time have found evidence of an ancestor of Tyrannosaurus rex in the Southern Hemisphere, a discovery that could shed light on tyrannosaurs' evolutionary lineage, which many scientists had thought was restricted to the Northern Hemisphere after the continents began to separate. Tyrannosaurs had been documented only in Asia, Europe and North America, but a hip bone discovered in Australia could have come only from a tyrannosaur, researchers have concluded.

IT'S NOT JUST NATURE THAT abhors a vacuum; man does too. That sucking sound you hear is the noise made by thousands of young immigrants as they travel from the overpopulated Southern Hemisphere to the more prosperous Northern Hemisphere in pursuit of employment. The phenomenon is putting pressure on economies from Oslo to Okinawa, and it is fueling raucous worldwide debates about immigration and motherhood.

The north and south poles on Mars look very different from each other, and scientists now think they know why: Circulation patterns in the Red Planet's very thin atmosphere tend to keep all the water in the north, leaving the south pole high and dry. The exploration of Mars by unmanned spacecraft has shown that the northern hemisphere has a large polar cap made up mostly of frozen water while the southern hemisphere has a much smaller cap made up...

The winter warming of the Northern hemisphere in recent years is ultimately caused by global warming, but the more proximate cause is change in the jet stream, NASA researchers report in today's issue of the journal Nature. Although mean global temperatures have risen by less than 1 degree Fahrenheit since the 19th century, winter temperatures in the Northern Hemisphere have climbed by as much as 9 degrees in the last 35 years.

The years 1997, 1995 and 1990 were the warmest in the Northern Hemisphere since the days of Christopher Columbus, according to researchers from the University of Massachusetts at Amherst. And the researchers say that they found evidence that rising levels of greenhouse gases are probably responsible. Geoscientist Michael Mann and his colleagues reconstructed annual average temperatures back to the year 1400 and found no year warmer than those three, they report in today's Nature.

Tyrannosaurs may have stalked far more of the globe than previously thought. Scientists for the first time have found evidence of an ancestor of Tyrannosaurus rex in the Southern Hemisphere, a discovery that could shed light on tyrannosaurs' evolutionary lineage, which many scientists had thought was restricted to the Northern Hemisphere after the continents began to separate. Tyrannosaurs had been documented only in Asia, Europe and North America, but a hip bone discovered in Australia could have come only from a tyrannosaur, researchers have concluded.

The winter warming of the Northern hemisphere in recent years is ultimately caused by global warming, but the more proximate cause is change in the jet stream, NASA researchers report in today's issue of the journal Nature. Although mean global temperatures have risen by less than 1 degree Fahrenheit since the 19th century, winter temperatures in the Northern Hemisphere have climbed by as much as 9 degrees in the last 35 years.

Ozone recovery over the Northern Hemisphere may take longer than expected if recent winters are any indication, an analysis by European scientists concludes. The European researchers used weather balloons to measure ozone concentrations over the Northern Hemisphere during the winter of 1995-96. Arctic ozone reached record lows that year, dipping at some points to 64% of normal levels.

Spring has been arriving earlier in the Northern Hemisphere--possibly due to global warming--with the result that the growing season in many countries is a week longer than 20 years ago, scientists announced Wednesday. It is the first time that such a widespread increase in the growing season has been reported, the scientists said.