Check out the new “GeogSpace” section to our website here which includes links to interactive geography tools and articles that display the diversity of geography today!




Map of the week August 18th-24th

Which state has the highest concentration of Facebook users? Find out on this week’s map of the week! Also, click here to like us on Facebook so you can state up to date with everything happening at AGS! 

FB users in each state in the US

Scientists pinpoint drivers behind extreme weather in new study

Waves in the jet stream, increase the likelihood of extreme weather.  (Image: NASA)

Waves in the jet stream, increase the likelihood of extreme weather.
(Image: NASA)

In the messy, chaotic atmosphere of our planet meanders the jet stream, a wiggly belt of air circling the mid-latitudes. As the belt moves south, it pulls cool air from the Arctic toward the tropics. Then it switches direction, pulling warm air from the tropics toward the poles.

Sometimes, in response to natural climate patterns, the jet stream becomes abnormally wavy. Such amplified waves have coincided with heat and cold waves, droughts and flooding across the world, according to a study published yesterday in Nature Climate Change.Take the past winter in North America, for example. The eastern and central United States were plunged into a deep freeze, Alaska was unusually warm and California was dry. Above the continent, the jet stream was indulging in some unusual behavior. Its northward swing was so big that it sucked warmer air right into Alaska, which was positively balmy in the wintertime. Then, the wave turned toward the south with a big swing, bringing Arctic air into the central United States.Weather watchers have always assumed that the jet stream might account for some weather extremes, but this is the first paper to demonstrate that conclusively.

“I think [the paper] has done a fabulous job of basically documenting a relationship that most people believed existed,” said Jennifer Francis, an atmospheric scientist at Rutgers University, who was not affiliated with the new study. “[It] has shown that, indeed, many of the extreme events that have occurred in the past, going back to the late 1970s, are associated with very large waves in the jet stream.”

The study is particularly relevant in the context of a controversial hypothesis championed by Francis that the jet stream will get more wavy in the future with climate change (ClimateWire, April 3).

Understanding the climate link requires knowledge of the jet stream’s evolution, which most people do not have, because, “why would you?” asked James Screen, a climate researcher at the United Kingdom’s University of Exeter and the lead author of the new study, with a laugh.

A possible connection to Arctic warming?

The jet stream, also known as “Rossby waves,” is result of the Earth spinning. As the planet turns, blobs of air begin moving from west to east. As the blobs encounter accidents of topography — such as a mountain range — they deflect, sometimes toward the Equator.

Another little-known fact is that the Earth — and the air above — has more spin at the poles than at the Equator. A blob from the north that is deflected south will find itself in a region with less spin. It then attempts to return to the latitude it belongs and curves back. But, it overshoots its mark and has to turn back southward. A wavy jet stream forms.

When the waves get very large, they move more slowly. That means the weather they create also move more slowly, which leads to very extreme weather that hangs around oppressively for weeks.

Francis has suggested that the frequency of the wavy patterns in the jet stream is increasing as the Arctic warms due to climate change. But there is not enough data to prove this hypothesis.

“No one has come out and said this is wrong and presented results showing that it’s wrong,” Francis said. “But there is uncertainty at this point whether we can see this happening in the real world or not.”

If the theory is true, then the new study would seem to suggest that heat and cold waves would occur more frequently in the future.

Droughts, extreme rainfall and temperature extremes

Screen, the primary author, stressed that his new study does not deal with the controversial link between the Arctic, climate change and the jet stream. Rather, it simply uses historical weather data to connect the jet stream and extreme weather, which is the noncontroversial part of the equation.

Screen and his colleagues identified 40 extreme weather events, including heat waves, cold temperatures, droughts and heavy rainfall, that occurred since 1979 throughout the world. That date was chosen because satellites began providing quality meteorological data around then.

The scientists then used computer models to reconstruct the jet stream as it must have existed during those weather events. They found that, in general, extreme weather appeared to coincide with amplified jet streams.

The type of extreme weather appeared to differ with geography. This is because the jet stream is just one link in the chain of climatic events influencing local weather.

The study found that the jet stream increased the likelihood of hot months in western North America and central Asia, and extreme cold months in eastern North America. It also increased the likelihood of droughts in central North America, Europe and central Asia, and extreme rainfall in western Asia.

This story was originally written for Climate Wire and was republished with permission here.

AGS endorses and commends Rockefeller’s 100 Resilient Cities

The Rockefeller Foundation has so far named 32 of the 100 cities that will make up the “100 Resilient Cities” initiative. The American Geographical Society, which is one of the world’s oldest and leading organizations committed to geographical leadership, announced that it is endorsing the “100 Resilient Cities” initiative and commends the Rockefeller Foundation for its foresight in helping urban centers prepare for the 21st century.

100 Resilient Cities (100RC) is dedicated to helping cities around the world become more resilient to the physical, social and economic challenges that are a growing part of the 21st century. 100RC supports the adoption and incorporation of a view of resilience that includes not just the shocks – earthquakes, fires, floods, etc. – but also the stresses that weaken the fabric of a city on a day to day or cyclical basis. Examples of these stresses include high unemployment; an overtaxed or inefficient public transportation system; endemic violence; or chronic food and water shortages. By addressing both the shocks and the stresses, a city becomes more able to respond to adverse events, and is overall better able to deliver basic functions in both good times and bad, to all populations.

“Resilience is the application of what we study in geography and exemplifies the work in which the AGS has always been involved” noted Dr. Joseph Wood, AGS Councilor, and Provost at the University of Baltimore.

“The imperative before us is how we, as global citizens, can adapt to changing local and regional environments even as we grow, prosper, and consume resources at an alarming rate. Resilience in its paramount form is about shaping—and reshaping—the built environment to ensure economic success and, indeed, cultural survival for future generations. This initiative by the Rockefeller Foundation is perhaps the most important step so far, to frame the discussion which address this critical area for the 21st century,” added Dr. Wood.

Read the full press release at: or like us on Facebook to stay tuned to all our updates and latest news stories.

2014 World Cup Contenders and Past winners

This week’s ‘Map of the Week’ shows past winners of the World Cup and possible contenders for this years title. Who do you think will win this year’s title? Will Brazil retain the title of the team that has won it the greatest amount and make it a equal number of wins with European teams? Or will a European team win and further advance their lead?

2014 World Cup Contenders and Past winners