A warmer Arctic could permanently affect the pattern of the high-altitude polar jet stream, resulting in longer and colder winters over North America and northern Europe, US scientists say. The jet stream, a ribbon of high altitude, high-speed wind in northern latitudes that blows from west to east, is formed when the cold Arctic air clashes with warmer air from further south. The greater the difference in temperature, the faster the jet stream moves.
According to Jennifer Francis, a climate expert at Rutgers University, the Arctic air has warmed in recent years as a result of melting polar ice caps, meaning there is now less of a difference in temperatures when it hits air from lower latitudes. “The jet stream is a very fast moving river of air over our head, but over the past two decades the jet stream has weakened. This is something we can measure,” she said Saturday at a meeting of the American Association for the Advancement of Science. As a result, instead of circling the earth in the far north, the jet stream has begun to meander, like a river heading off course. This has brought chilly Arctic weather further south than normal, and warmer temperatures up north. Perhaps most disturbingly, it remains in place for longer periods of time.
Image Credit: NASA Goddard Space Flight Center Scientific Visualization Studio [x]
xtanti asked: Hi Michael, Greetings from Indonesia. I enjoy your blog because I'm interested to learn about environment. As you might heard recently there're two big volcano eruptions in our country. Do you think they can influence the global weather? I've read in a journal that Krakatoa and Tambora eruptions in 19th century created global wheather changes then. Or the two recent eruptions are not significant enough for global weather? (I'm sorry if my English is not well structured) Yeni
Your English is just great! Yes, the gas and soot from erupting volcanoes do influence the climate for short periods of time. The volcanoes erupting in Indonesia right now are not getting the media coverage they deserve. Nearly 100,000 people have been evacuated, airports are closed, and the images of ash covering everything are amazing.
Mike Gunson, atmospheric chemist and director of the Global Change project at NASA has a better answer:
Can one blast from a volcano affect readings over most of the globe for an extended time?
Overall, volcanoes release about 5 percent of the equivalent amount of CO2 released by humans. Quite small. However, about once every 20 years there is a volcanic eruption (e.g., Mt. Pinatubo, El Chichon) which throws out a tremendous amount of particles and other gases. These will effectively shield us enough from the sun to lead to a period of global cooling. They typically dissipate after about two years, but the effect is nearly global.
That said, I’m not sure where to find the estimates of how these two big volcanoes will affect climate. Climate “forcings” are not my area. Maybe JAXA?
Surface temperature measurements are affected by short-term climate variability, and recent warming of deep oceans.
Why doesn’t the temperature rise at the same rate that CO2 increases?
The amount of CO2 is increasing all the time - we just passed a landmark 400 parts per million concentration of atmospheric CO2, up from around 280ppm before the industrial revolution. That’s a 42.8% increase.
A tiny amount of CO2 and other greenhouse gases, like methane and water vapour, keep the Earth’s surface 33°Celsius (59.4°F) warmer than it would be without them. We have added 42% more CO2 but that doesn’t mean the temperature will go up by 42% too.
There are several reasons why. Doubling the amount of CO2 does not double the greenhouse effect. The way the climate reacts is also complex, and it is difficult to separate the effects of natural changes from man-made ones over short periods of time.
As the amount of man-made CO2 goes up, temperatures do not rise at the same rate. In fact, although estimates vary - climate sensitivity is a hot topic in climate science, if you’ll forgive the pun - the last IPCC report (AR4) described the likely range as between 2 and 4.5 degrees C, for double the amount of CO2 compared to pre-industrial levels.
So far, the average global temperature has gone up by about 0.8 degrees C (1.4 F).
“According to an ongoing temperature analysis conducted by scientists at NASA’s Goddard Institute for Space Studies (GISS)…the average global temperature on Earth has increased by about 0.8°Celsius (1.4°Fahrenheit) since 1880. Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20°C per decade.” Source: NASA Earth Observatory
cazalis asked: Professor Richard Lindzen was on Al Jazeera's Head to Head recently. Did you see it? And what were your thoughts on the debate and his position?
Thanks for following me all this time. Lindzen is a researcher of atmospheric physics at MIT. He basically applies complex mathematical equations (via computer modelling [vs direct observation]) and makes inferences about the earth’s atmosphere.
His focus is atmospheric tides, which are similar to oceanic tides. Pretty interesting for about 5 minutes.
Lindzen is often portrayed as a climate denier, but this is not true. He regularly states that humans do affect long term temperatures by emitting carbon.
The main reason he’s called a denier is because he disagrees with the projected impacts from the well known science, models, and consensus. He thinks the impacts are overstated. He provides no evidence for this. His argument is strange, and journalists do not know how to parse his position. This is why Lindzen gets so much play - he has an obtuse argument sandwiched between big words.
He basically argues that since scientists cannot predict the future of climate with 100% accuracy, he will not predict the future ever, and therefore no one else should either. Sort of like saying we know snake venom is dangerous. But since we cannot predict what it will do to you with 100% certainty, we should not worry about it. It’s a very strange argument to make.
As far as I can tell, he has not explained or published his evidence for his argument. So, no one in the field of climate change takes him seriously. He’s great at PR though (thus his appearance on Head-to-Head). Also, journalists are (generally) very stupid when it comes to math and science. So, he takes advantage of this.
Looks like a substantial course correction in climate change research. It seems species that were once thought “safe” from changes in climate are more vulnerable than expected. It also seems to add support for the controversial planetary boundaries theory.
OSLO (Reuters) - Many species of birds, amphibians and corals not currently under threat will be at risk from climate change and have been wrongly omitted from conservation planning, according to a major new international study.
The Amazon rainforest was among the places where ever more types of birds and amphibians would be threatened as temperatures climbed, it said. Common corals off Indonesia would also be among the most vulnerable.
Overall, up to 41 percent of all bird species, 29 percent of amphibians and 22 percent of corals were “highly climate change vulnerable but are not currently threatened”, the team of scientists wrote in the journal PLOS ONE.
"It was a surprise," said Wendy Foden, of the global species program of the International Union for Conservation of Nature (IUCN) who led the study. Experts had expected far more overlap between species threatened now and those vulnerable to global warming.
Conservation priorities should be revised to take account of the emerging climate risks, for instance to decide where to locate protected areas for wildlife, the scientists wrote.
Most impressive (to me) is how well written it is. Check out how they describe and compare three systems:
El Niño and La Niña episodes, for example, result from rapid changes in the sea-surface temperature in the equatorial Pacific Ocean. They influence weather patterns around the world through the subsequent large-scale interactions and transfers of heat in the coupled ocean-atmosphere system. Other patterns affect the climate by strengthening or weakening high-altitude air currents known as jet streams.
The closely related Arctic Oscillation and North Atlantic Oscillation often affect the northern hemisphere winter. Since the 1990s, these two oscillations have remained mostly in a positive phase, which is associated with warmer and wetter winters in northern and central Europe and the eastern USA, drier winters in the Mediterranean and cold, dry conditions over northern Canada and Greenland.
Unlike these natural back-and-forth oscillations, human-caused climate change is trending in just one direction. This is because atmospheric concentrations of carbon dioxide, methane, nitrous oxide and other greenhouse gases are increasing steadily, due to human activities. According to the WMO Greenhouse Gas Bulletin, global-average atmospheric concentrations of carbon dioxide rose to 389 ppm in 2010 (an increase of 39 per cent compared to pre-industrial times), methane to 1 808.0 ppb (158 per cent) and nitrous oxide to 323.2 ppb (20 per cent).
This changing composition of the atmosphere is causing the global average temperature to rise, which, in turn, exerts a significant influence on the hydrological cycle and leads to other changes in climate and weather patterns.
Great read and video of the researchers in Mongolia.
Eight hundred years ago, relatively small armies of mounted warriors suddenly exploded outward from the cold, arid high-elevation grasslands of Mongolia and reshaped world geography, culture and history in ways that still resound today. How did they do it?
Tree-ring scientists at Columbia University’s Lamont-Doherty Earth Observatory have worked in Mongolia since 1995. In 2010, Lamont researcher Neil Pederson and Amy Hessl of West Virginia University were seeking old trees for a study of wildfire history. High in the Khangai Mountains, north of the steppe where the long-disappeared Mongol capital of Karakorum once lay, they explored a nearly solid-rock plain of hardened lava left by a volcanic eruption some 8,000 years ago. Growing out of fissures and thin soils were thousands of gnarled, stunted larches and Siberian pines–a tree-ring scientist’s treasure. Annual rings of many species reflect rainfall or temperature in predictable ways. These can be read like books; and trees in the driest, harshest sites like this are exquisitely sensitive to rain, live to extraordinary ages, and leave trunks that may stand for centuries after they die. They are truly ancient manuscripts, writ with a fine hand.
Pederson and Hessl analyzed 17 trees to chart a yearly record of rainfall back to 658 AD. They saw that from 1211-1230—the exact time of the Mongols’ rise—central Mongolia saw one of its wettest periods ever. That time also was unusually warm, as shown by a 2001 paper from other Lamont researchers.
Sea ice is any form of ice found at sea that originated from the freezing of sea water. It is the most visible feature of the Arctic Ocean, with its extent waxing and waning with the seasons. Ice thickness is highly variable, ranging from a thin veneer to tens of meters. While the existence of sea ice reflects the cold conditions inherent to high latitudes, sea ice also strongly modulates the energy budget and climate of the Arctic and beyond, particularly because it is white, and hence reflects much of the sun’s energy back to space (it has a high albedo) and also through acting as a lid, insulating the underlying ocean from a generally much colder atmosphere.
Historically, at its maximum extent in March, Arctic sea ice covered an area more than 15 million square kilometers, somewhat less than twice the size of the contiguous United States. The minimum extent, occurring in September, the end of the melt season, was typically around 7.0 x106 km2. However, as assessed over the modern satellite record spanning 1979 to the present, Arctic sea ice extent exhibits downward linear trends for all months, weakest in winter and strongest for September. The downward September trend appears to have accelerated over the past decade. Through 2001, the September trend stood at -7.0% per decade. Through 2012, it was more than twice as large at -14.3% per decade. The six lowest September extents in the satellite record have all occurred in the past six years, with September of 2012 setting a new low mark. Decreased summer ice extent has been accompanied by large reductions in winter ice thicknesses that are primarily explained by changes in the ocean’s coverage of thick multiyear ice (MYI). MYI is ice that has survived at least one summer melt season. In the mid-1980s, MYI accounted for 70% of total winter ice extent, whereas by the end of 2012 it had dropped to less than 20%. At the same time the proportion of ice older than 5 years declined from 50% of the MYI pack to less than 8%.
Ice loss is also contributing to strong rises in Arctic air temperature during autumn and winter, not just at the surface, but extending through a considerable depth of the atmosphere. As discussed, sea ice acts as a lid, insulating the underlying ocean from a generally much colder atmosphere. With less ice, the insulating effect is weaker, so heat can readily be transferred from the ocean to the atmosphere above. This strong warming, termed Arctic amplification, is starting to extend beyond areas of ice loss to influence Arctic land areas.
Continued loss of the ice cover is in turn likely to impact on patterns of atmospheric circulation and precipitation not just within the Arctic, but into middle latitudes; there is evidence that this is already occurring. The basic reason for this is that the outsized warming of the Arctic changes the atmospheric stability and temperature differences between the Arctic and lower latitudes. Finally, as the ice cover retreats, the Arctic is becoming more accessible for marine shipping as well as oil and natural gas exploration, increasing the economic and strategic importance of the region.
"A meteorite exploded above the Chelyabinsk region (of the Urals). The shock wave blew out windows in several places," but no meteor fragments hit the ground, an emergencies ministry spokesman told the Interfax news agency.
"According to the preliminary information, four people were injured by flying glass," the ministry added.
An agency report spoke of several injuries.
Witnesses cited by news agencies spoke of hearing loud explosions which led to panic among residents.
The Halley Research Station in Antarctica is run by the British Antarctic Survey. The station is used to conduct research into meteorology, glaciology, seismology, radio astronomy, and geospace science.
Recently, the program began focusing on anthropogenic climate change. Halley provides vital information for a global understanding of ozone depletion, polar atmospheric chemistry, sea-level rise and climate change.
The station is mobile, but will likely remain in place for years to come. It took four years to build, and delivered its first scientific research in 2012.
About 20 to 70 people work and live at the station throughout the year, depending on the season.
Background on living, working, research, history, the weather, and even a webcam: here
Curious about Halley’s governing institution, the British Antarctic Survey? Go here
About the architects. The station was designed by Hugh Broughton Architects, which specializes in extreme environment engineering for unique clients.
Our approach requires us to exercise the lateral thinking abilities of an architect to the full, taking us into new territories, exploring new forms of construction and drawing upon the full breadth of available technologies from a vast array of industries. This is epitomised by the success of our work for extreme environments, where we are one of the global leaders in the design of scientific research facilities in the Polar Regions. Via HBA
The folks at Skeptical Science wrote an epic take down / open letter to London Mayor Boris Johnson. Johnson embarrassed himself in an opinion-editorial published the UK’s The Telegraph. In it, the Mayor of one of the most powerful cities in the world claimed he doesn’t know a thing about science, yet his ignorance and lack of curiosity somehow allows him to understand how the entire earth’s climatic system works.
Epic take down is epic.
Higher temperatures cause increased water evaporation. Evaporated water forms more cloud cover. Add those clouds to winter, and you get more snow. The end. So, either the Mayor is a genuine ignoramus, or he’s chosen the drunken route of power, wishing to stay elected rather than take action and lead.
The letter is a great read. Here’s the beginning:
Open Letter to London Mayor Boris Johnson - Weather is not Climate
In your editorial, you acknowledge your lack of expertise on the subject, but defer to weather forecaster Piers Corbyn due to his alleged accuracy in predicting British weather (that accuracy being generally exaggerated, with manycounter-examples). However, irrespective of his accuracy in making weather predictions, Corbyn is not a climate scientist; weather forecasting and climatology are very different scientific fields. If your cardiologist informed you that you need open heart surgery, would you ask your dentist for a second opinion?
An unusual event playing out high in the atmosphere above the Arctic Circle is setting the stage for what could be weeks upon weeks of frigid cold across wide swaths of the U.S., having already helped to bring cold and snowy weather to parts of Europe.
An Arctic cold front was sliding south from Canada on Friday, getting ready to clear customs at the border on Saturday and Sunday, bringing an icy chill to areas from the Plains states through the Mid-Atlantic by early next week, including what promises to be a chilly second inauguration for President Obama.
Temperatures in Washington on Monday are expected to hover in the low 30s, only a touch milder than Obama’s first inauguration, when the temperature was 28°F.
Reinforcing shots of cold air are likely to affect the Upper Midwest, Great Plains and into the East throughout February, with some milder periods sandwiched in between.
Sudden stratospheric warming events occur when large atmospheric waves, known as Rossby waves, extend beyond the troposphere where most weather occurs, and into the stratosphere. This vertical transport of energy can set a complex process into motion that leads to the breakdown of the high altitude cold low pressure area that typically spins above the North Pole during the winter, which is known as the polar vortex.
The polar vortex plays a major role in determining how much Arctic air spills southward toward the mid-latitudes. When there is a strong polar vortex, cold air tends to stay bottled up in the Arctic. However, when the vortex weakens or is disrupted, like a spinning top that suddenly starts wobbling, it can cause polar air masses to surge south, while the Arctic experiences milder-than-average temperatures.
During the ongoing stratospheric warming event, the polar vortex split in two, allowing polar air to spill out from the Arctic, as if a refrigerator door were suddenly opened.