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Kimberlite Kimberlites are volcanic eruptions that start deep inside Earth’s mantle, at depths of hundreds of kilometers. At that depth, carbon dioxide may not easily fit into the available minerals, and might instead sit as a (supercritical) fluid, in-between larger mineral crystals.
The Greenhouse Effect and how humans are driving it in one measurement
We would not be here without the greenhouse effect. Without the atmosphere, the Earth’s climate would be a lot like the moon – over a hundred degrees C during the day, hundreds of degrees C below zero during the night. Sunlight is absorbed by the atmosphere and converted to heat, the atmosphere takes a while to let that heat out, acting like a greenhouse that keeps the dark side of the planet from freezing and enabling life as we know it to exist.
Gases in the atmosphere drive the greenhouse effect. Sunlight absorbed by the rocks on the surface converts to heat and that heat is radiated away as infrared light. The atmosphere is transparent to visible light (that’s why we can see the sun), but certain molecules absorb some wavelengths of light in the infrared. When that light is re-absorbed in the atmosphere, it is converted back to heat, holding onto the energy for longer and keeping things warm. That’s the essence of how the greenhouse effect works. When you have a cloudy sky, or a humid day at night - it tends to keep the surface warmer because the heat cannot escape out to space, same effect.
As the abundance of molecules in the atmosphere that absorb infrared light increases, more light should be absorbed and converted back into heat. That’s the basic logic that leads to the concept of climate change as a function of CO2 – add extra CO2 to the atmosphere and basic physics says it has to hold in more heat.
Because the earth’s atmosphere is a complicated place, full of clouds, water vapor, and other species, even though we know this physics, measuring the exact behavior of CO2 in the atmosphere has been a bit more difficult until now. This plot shows the exact behavior of CO2 measured in the atmosphere by satellites over a 10 year period and how additional energy is being absorbed as humans release more CO2.
A group of researchers led by scientists from Lawrence-Berkeley National Laboratory collected these 2 data sets in areas that commonly have clear skies - Southern Great Plains and the North Slope of Alaska. They measured specifically the emission of light at the wavelengths released by CO2 on those days – how much light goes out to space versus how much light is re-absorbed and converted back into heat. The higher the “radiative forcing”, the more energy CO2 is holding in the atmosphere and and the more is being sent back down to Earth.
Every year, CO2 goes down during northern hemisphere summer because there is more land area and more plants in the northern hemisphere, but it goes up again the next winter. On top of those yearly oscillations, there are short-term changes from events like wildfires and weather. Finally there is a long-term trend where every year more energy is absorbed - that’s the part humans are doing. Pump more CO2 into the atmosphere by burning fossil fuels, the CO2 absorbs more energy, converts it to heat, and the Earth’s atmosphere has to figure out what to do with all that new energy. Note how the grey curves for measured CO2 in the atmosphere at the sites and the red curves for the atmospheric spectra themselves are highly correlated, as they should be.
This is the greenhouse effect and the way CO2 contributes to climate change captured in one single plot.
-JBB
Image credit and original paper: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14240.html
The Champagne Pool
This hot spring is found in an area known as the Waiotapu geothermal area on New Zealand’s North Island.
The hot spring sits in a crater 65 meters across and reaches temperatures of ~75℃. The vivid colors around the edge are produced due to elements that are dissolved in the hot waters as they travel through the ground.
Amber reveals long past climates
Recent work by a team at Innsbruck University analysed 538 samples of the golden gem with a wide range of ages, from the Triassic of 220 million years back to recent quaternary copal (an immature form of amber). They used carbon isotopes to tell them something about atmospheric compositions in the deep past, in particular about the proportion of oxygen in the air and how they changed during this long period. Amber was used because it changes little isotopically as it matures, serving as a useful proxy for something hard to measure by other means. Carbon 13 is taken in by plants in different proportions depending on the oxygen content of the atmosphere. Comparing the ratios of C12 to C13 in the samples allows the oxygen content to be deduced.
They were surprised to find that the air that dinosaurs breathed was alot less oxygen rich than had been supposed. Our current atmosphere contains 21% oxygen, while Mesozoic amber indicates a proportion of only 10-15% was present. Some have posited that high O2 levels might have been responsible for the gigantism of dinosaurs, as seems to have been the case for the huge insects of the Carboniferous, but this hypothesis is now cast in doubt.
More generally, low oxygen seems to correlate with high atmospheric carbon dioxide, and warmer climate, such as the hothouse world of the Mesozoic. The team suggests that high levels of volcanism may have fed CO2 into the air, causing a decrease in oxygen due to increased chemical weathering capturing it into oxides. They attribute the cooler climates that have prevailed since the later Eocene to a general decrease in volcanic activity.
Image credit: Ryan C. McKellar, Cretaceous amber with trapped conifer leaves from Alberta in Canada. http://www.uibk.ac.at/public-relations/presse/archiv/2013/466/ http://www.zmescience.com/science/geology/oxygen-amber-levels-19112013/ http://www.redorbit.com/news/science/1113005968/amber-gives-clues-into-earth-atmosphere-111813/
Original article, paywall access: http://www.sciencedirect.com/science/article/pii/S0016703713003906
Old trees make the best carbon sinks
A new study published in last week's issue of Nature shows that, contrary to popular assumptions, it is old trees rather than young that convert the most carbon into biomass. The work has important implications for understanding the global carbon cycle, underlines the vitality of conservation of the remaining old growth forests worldwide and for developing forestry management strategies to mitigate climate change through systems such as carbon offsetting.
Previously, young fast growing species were thought to transform the most carbon into biomass, with growth rated believed to slow and eventually stop as the trees aged. The new global study by a team of 38 scientists overturned this belief, demonstrating that the larger older trees accounted for a third of annual mass growth in forests while amounting to a mere 6% of the trees. They showed that large old trees could add as much as the volume of a whole medium tree to their biomass yearly, and that their growth rate increased with age. The work was based on an analysis of nearly 675,000 trees of 400 species spread worldwide, and confirms another paper published in 2010 that focussed on eucalypts and sequoias. Another study in 2012
The latest study is wider ranging, and confirms that preservation of these rare and important trees is important for more than merely aesthetic reasons. As well as planting many young trees, middle aged ones should not be cut, and the cycle of using fast growing commercial trees such as pine as carbon offsets will not yield as high benefits as preserving existing forests and allowing the continued growth of older trees. Sadly, old trees are disappearing fast all over the world, mostly due to pressure on habitats and the increase in commercial forestry and deforestation in areas such as the Amazon and Borneo.
Loz
Image credit of General Sherman, the largest specimen in Sequoia National Forest: Jim Bahn http://www.theguardian.com/environment/2014/jan/15/trees-grow-more-older-carbon http://www.smh.com.au/environment/climate-change/oldgrowth-forests-seen-more-valuable-as-carbon-sinks-study-20140116-30vvc.html http://www.foresteurope.org/es/node/499 Original paper, paywall access: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12914.html 2010 study: http://www.sciencedirect.com/science/article/pii/S037811270900872X
Can humanity maintain a stable climate?
Much of human civilization has been built under the assumption that the climate will remain roughly stable. Cities are built where they are because water and food supplies will remain constant. The more the climate changes due to increasing greenhouse gas concentrations in the atmosphere, the greater the costs of responding will be.
This logic led negotiators at the Paris Climate Talks last year to set an arbitrary goal of avoiding temperature increases larger than 2°C compared with temperatures before the industrial revolution. Some countries in those talks pushed for even more stringent standards, with a goal of 1.5°C temperature increase being the strongest standard referred to in press reports. For comparison, the difference in temperature between the last ice age and today is about 4-5°C.
As of right now, Earth is nearly 1°C hotter than it was before the industrial revolution. 2 new studies just published this week argued that the Paris Agreement may be no where near enough to meet these standards. In fact, one of these studies argues that based on the carbon already released to the atmosphere, it is possible humanity has already committed to over 3°C of temperature change.
The first study focused on economic and development statistics. They combined historical records of population growth with estimates of how global economies will reduce the amount of carbon released – referred to as decarbonation. Finally, they included an estimate of the sensitivity of the climate system to increasing carbon, and found that based on historical trends and the commitments of the Paris agreement, they expected the planet to warm from 2.0–4.9 °C over the next century, with a median temperature increase of 3.2°C. They estimate only a 1% chance that current trends will keep temperatures from going up 2°C or less.
Interestingly, they find that since most population growth is happening in Africa and those areas use the least carbon per capita, population growth is not a major factor in whether or not Earth exceeds that 2°C threshold. Basically, it’s all about how rapidly we can decarbonate the global economy, and historic trends suggest we will fail.
The second study steps back and focuses on a different property. Rather than assuming the sensitivity of the carbon system, they used new estimates of how Earth’s temperature responds to increasing greenhouse gases to give a range of sensitivities. In this study, they find that the carbon released already, without a single additional year’s CO2 increase, has already committed the planet to at least 0.9-2.3°C of warming, with a 10% chance that the already released CO2 is enough to push the planet past the Paris agreement goals.
In summary, both of these studies are worrisome. The more we disrupt global climate, the greater the costs will be in money and lives. Although the Paris agreement was a start, as it did commit much of the world to decarbonation, both these studies suggest that far more needs to be done. However, there is some remaining hope implied by both of them.
The one thing not considered in the statistical study was that maybe, just maybe, historical trends are not a good model for decarbonation. We’ve seen countries like the United States effectively grow their economies over the past few years without large increases in carbon usage, while others like China have grown their economies with massive increases in carbon release. The US and EU experiences show that economic growth can be separated from increased carbon release. If, through agreements such as Paris, humanity can become even better at decarbonation, we might still have a shot at meeting that threshold. But of course on the other hand…the work for both of those studies was done before the U.S. pulled out of the Paris agreement, and it remains to be seen how much the US government can push carbon emissions upwards.
There is nothing magic about the 2 °C line – it was chosen as a goal to shoot for. The farther the planet goes past that number, the more severe the consequences are likely to be.
-JBB
Original studies: https://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3352.html https://www.nature.com/articles/nclimate3357
Image credit: http://bit.ly/2hlbobO
WHEN YOU DRINK YOUR CHAMPAGNE FOR NEW YEAR'S…
Give a toast to the remarkable geographic, geologic, climatic and soil conditions without which your champagne would be … flat.
Champagne, the province where the bubbly was born. The “father” of the bubbly was Dom Perignom, a monk actually, who in the 17th century put together the knowledge-base required to make a good wine with the special fermentation, special mixture of grapes, and brilliant addition of sugar to create sparkling wine. The sugar is essential for dissolving the carbonate gas in the wine, and once this gas is in it, the wine needs something special to hold the fizz inside the bottle, so he apparently also invented using a cork as a bottle stopper.
The Earth of Champagne… Why is it so special? --At the 49th parallel, this is one of the most northern of the world’s major wine producing areas. This gives it an advantage of longer days in the summer when the sun is all important to the vine. --The average rainfall is about 50 cm, ooh la la, perfect! --The average temperature, even in the summer, is a tad low at 18C in July. However, only at such cooler temperatures are high acidic levels reached in a grape, and this acidity makes for a perfect sparkling wine. --The forests in the area are an essential part of the wine environment, stabilizing temperatures and soil moisture, prolonging the ripening season despite what would be “too cold”. --The geology… oh, you were expecting I’d get into the geology of the province, weren't you?
The bedrock of the wine district is chalk. Chalk is a limestone sediment made of the remains of the tiniest of oceanic microfossils, highly compressed – after all, you can write on a blackboard with it. At Champagne, the chalk was deposited in the Cretaceous, in a tropical sea closer to the equator than present day France, and apparently a lot of small squid-like creatures called belemnites also were incorporated into the deposits. With the incessant drifting of tectonic plates, the region slowly moved towards the north, then, about 30 million years ago, was uplifted to surface, fracturing the solid chalk into soil-friendly sizes, then again about 11 million years ago when the chalks were raised to form the welcoming landscape that would make the wine country. The convergence of the weather conditions with these uplifts created a two-tier chalks geology: the substrata is solid chalk, some of which provides the optimal settings for wine cellars, while the surface is made of the tectonically and erosionally broken rubble of chalk, especially those belemnite fossils, that apparently work their way up through the chalk like a splinter from your finger.
These chalky soils are heaven on earth for the grapes of Champagne: their light color is said to reflect much of the too-hot sun in the summer, while retaining the heat in the winter: their ability to retain moisture in fragments such as those in the belemnite fossil rubble is essential, while being broken-up they drain excess waters easily. And their chemistry – we’ve done this before, I think: calcium carbonate plus acidic water (or wine) reacts to release carbon dioxide: Voila! The Bubbly!
New Years’s Eve is not the time to debate whether the wines of Champagne really are the most superb on Earth: surely you have some favorites from California, from New Zealand, from Crete and Santorini, and there’s a bubbly from Rhodes that’s, well, truly decadent. And I hope you’ve had the opportunity to taste wines from all over the earth and discover that yes, there does seem to be a distinct “taste” that varies with the lands that produce the wine. Indeed, the extraordinary geology of wine producing areas has developed into a new specialty field over the last few decades.
Wine and Champagne and “bubblies” in particular are the very flavor of the Earth that produces them.
Cheers! and Happy New Year! Annie R.
The photo was downloaded from: http://www.russellgehlingwines.com.au/champagne-france-c-27.html and it is available as a screen saver from: http://m.wallpapers-catalog.com/panoramic-view-of-vineyards-champagne-france-wallpapers.1600x1200.download.html
If you haven’t been sipping too much of that sparkling wine allready, try reading: http://suite101.com/article/the-origin-of-chalk-in-the-champagne-region-a130806#ixzz2GXtWShjY http://www.dartblog.com/data/2010/11/009215.php http://www.partnerswine.com/#!champagne-france/co30 https://www.champagnegallery.com.au/champagne-science/viticulture/soil---the-magic-of-chalk/ http://www.terroir-france.com/wine/champagne_winemaking.htmhttp://books.google.gr/books?id=gt517z302YcC&pg=PA68&lpg=PA68&dq=chalky+soil+of+champagne&source=bl&ots=LCmxwdQTq7&sig=JMAXwTqRDfKJPgZMwHLrrHQBeI4&hl=en&sa=X&ei=rkXgUPTlN4XhtQaroIG4BA&redir_esc=y
Martian Gullies
If you have been following any of the recent advances in planetary exploration, you must have come across several missions that have been sent to our neighboring planet – Mars. Discovering evidence of life and water have been the primary objectives of these missions. Images of the surface of Mars show geological evidence of water flow (network of narrow channels cut into steep slopes) across both the hemispheres. These channels resemble gullies carved by flowing water we see in the hill-country on our planet and we interpreted that this was evidence for past liquid water activity in Mars too. However, the planet Mars has a very low atmospheric pressure (7.5 millibars) compared to the average air pressure on Earth (1013 millibars) and so it impacts the stability of liquid water on the surface of Mars.
Among the many missions sent to Mars was NASA’s Reconnaissance Orbiter that was launched in 2005 to provide evidence that water persisted on the surface of Mars for long periods of time. Martian gullies were first discovered in 2000, and since then some of the channels in these gullies have undergone visible morphological (structural) changes over even short intervals such as a Martian year (~686 Earth days). If the formation of these channels with flowing water is ruled out, what other mechanism might actively create these deep network of channels along the slopes of Mars?
To address this question, plenty of images captured by instruments aboard the Reconnaissance Orbiter were examined and analysis show that the mineral composition of the sediments deposited at the bottom of these gullies matched the rocks at the top (upstream). The sediments also did not show any evidence of gypsum, calcite or clays which are hydrated minerals that form when rocks interact with water. This clearly rules out the presence of flowing water. Instead there were observations of seasonal accumulation of carbon-dioxide and water frost in these gullies. When carbon-dioxide sublimates it has the potential to destabilize rocky materials and can result in gas-lubricated debris flows down slopes. Observations suggest limited role (or - not at all) of water in the formation of Martian gullies and support a strong role played by carbon-dioxide – frost driven processes.
Images: Giant gullies in the Southern Highland – HiRISE Lunar & Planetary Laboratory - http://bit.ly/2c7PIsX Hadriaca Mons (caldera) - ESA/DLR/FU Berlin - http://bit.ly/2bBsIAU
Sources: http://bit.ly/2bBsIAU http://bit.ly/2bV1CYy http://go.nasa.gov/2c44thF http://bit.ly/2bBe6qd http://go.nasa.gov/1gjk1ht
Champagne Pool, New Zealand
A dip in champagne pool, a glass of champagne, or both? Let's stick with the first option. As attractive as this geothermal pool looks, it'd be a shame to perish in 75 °C (167 °F) acidic water.
Resting in a orbicular crater in the Waiotapu geothermal region on the North Island of New Zealand, Champagne Pool is one of the largest hot springs in all of New Zealand. Its geothermal fluids are rich in primarily CO2, H2S, other sulfide compounds. In addition, the pool contains a fairly large concentration of chloride ions, containing 1800 parts per million.
Its 3 acre surface is encrusted with sinter, a calcium or silicon based deposit of sediment. Note the rim next to the water in the image. The sinter creates a rim all around the perimeter of the lake, except for the eastern portion where the water overflows over Primrose Terrace. In some cases, this rim can be as tall as 1 foot high. Because of the high concentrations of sulfur and heavy metals, the water in certain areas appears to be a red-orange rusy color
Why the phenomenal colors you may ask? Because of the high concentration of sulfur and various heavy metals, many red-orange compounds are formed, making the water appear to be this color in certain locations, depending on the depth. These deposits include orpiment, realgar, and stibnite.
This lake emits high, bubbling levels of carbon dioxide. In a way, it resembles the fizzing nature of a glass of champagne, thus earning this pool quite an aesthetic label.
Be sure to check out the coordinates of this lake - in satellite view, the water is barely visible due to the produced clouds of CO2: -38.358919, 176.369275
--Sam J.
Image Credit: Christian Mehlführer, Wikipedia Commons
References:
(1) http://tinyurl.com/cy8gc77 (2) http://epod.usra.edu/blog/2010/01/champagne-pool.html (3) http://www.sciencedirect.com/science/article/pii/S0009254103003152 (4)http://link.springer.com/article/10.1007/s00792-007-0073-2
Lake Nyos.
In the Northwest Region of Cameroon is a crater lake called Lake Nyos. It may look like an ordinary lake but in August 1986 this lake released a massive cloud of carbon dioxide killing over 1700 people and about 3500 livestock in the surrounding areas.
A pouch of magma exists below the lake. This magma converts the water into carbonic acid by depositing certain amounts of carbon dioxide into the water.
The 1986 disaster was a result of a limnic eruption (commonly referred to as lake overturn). This is an extremely rare type of natural disaster. Small amounts of carbon dioxide gather together to form a large pocket until it suddenly erupts, releasing this CO2 into the surrounding areas. These eruptions have been known to cause small tsunamis as the carbon dioxide that rises displaces the water. It is believed, by many scientists around the world, that landslides, volcanic activity or any kind of explosions can trigger a limnic eruption.
To prevent another disaster, in 2001 a tube was installed to draw water from the bottom of the lake to the top. This method allows the carbon dioxide to escape in small, safe amounts. In 2011, another two tubes were added to assist in the degassing of the lake.
♞Renesh T
Image Credit:
http://s281.photobucket.com/user/Lampedusa/media/Cameroon_Lake_Nyos_2009/IMG_6442.jpg.html
Further reading and references:
http://vulcan.wr.usgs.gov/Glossary/Lakes/description_volcanic_lakes_gas_release.html
http://news.bbc.co.uk/onthisday/hi/dates/stories/august/21/newsid_3380000/3380803.stm
http://www.iomcworld.com/ijcrimph/files/v01-n01-01.pdf
http://www.nytimes.com/2001/02/27/science/trying-to-tame-the-roar-of-deadly-lakes.html
Carbon Dioxide Leak
This is an aerial photograph of the East African Rift System shot by an astronaut on the International Space Station on January 14th, 2012. This is one of the great tectonic features of Africa, caused by fracturing the Earth’s crust. This image shows numerous nearly parallel fault lines (the fault scarps are the dark lines on the image that are a result shadows cast by the late afternoon sun) that occupy the floor of the valley. These faults are a result of slow separation of plates of the continental crust which is deforming the surface of the Earth in this region.
We are aware of carbon emissions from the Earth’s interior through degassing of active volcanoes. However, this is not the only process that releases carbon dioxide into the atmosphere from the upper mantle or lower crustal magma bodies. A recent study published in Nature Geoscience has shown that carbon dioxide is being released from these deep fault lines that are far away from active volcanic centers. Scientists have quantified the carbon dioxide released from the East African Rift zone to 71 megatons every year. This value is comparable to the carbon dioxide leaking from volcanic chains across the sea beds along which new ocean floor is created.
Although carbon dioxide plays a major role in modulating the Earth’s climate, we have remained unaware of all the processes governing the natural fluxes of carbon between the Earth reservoirs and the atmosphere. This discovery gives scientists a more complete picture of natural sources of atmospheric warming carbon dioxide. Along with the East African Rift Zone, there are other continental rift zones in our planet such as the Basin and Range in the United States and the Eger Rift in central Europe. This discovery also suggests that during the widespread continental rifting during the Cretaceous, diffuse degassing along the continental rifts were the main source of the carbon dioxide to the atmosphere, which dramatically modified the climate of the Earth.
The newly discovered source doesn’t play a major role in influencing climate as much as human driven emissions. Although 71 megatons of carbon dioxide seems like a large figure, it is still on the order of 500 times smaller than human outputs.
Image Source: ISS Crew, Johnson Space Center http://go.nasa.gov/1NEuywo
Source: http://bit.ly/1nrqv0V http://bit.ly/1OTsODx
Steam and ash
Volcanic explosions such as Etna's ongoing burp (see http://on.fb.me/1QatBmb) are powered by degassing magma. Deep underground and under pressure, substances such as carbon dioxide, water and sulphur dioxide are dissolved in the molten rock, but as it rises towards the surface and the pressure decreases, the magma's capacity to hold them in solution decreases, and bubbles start to form. As they expand, the volume of the magma and the pressure it creates on the overlying rocks increase until the breaking point is reached and it explodes out onto the surface, degassing as it goes. Steam and fragmented ash fly out, sometimes accompanied by large globs of molten lava or country rock carried to the surface as the magma rose. Here the steam is brilliant white, followed by a burst of brown-grey ash illuminated from below by the lava, while stars quietly dot the background.
Loz
Image credit: Marco Restivo/Barcroft Media
Record after record after record
As the 2015 El Niño has built, the planet has broken one temperature record after another. All of the available numbers for August are in and like several of the previous months, August 2015 was the warmest August on record, following the warmest month ever recorded in July 2015.
Rather than showing another map of the global temperature, I found this chart did a spectacular job of illustrating how far above the long-term temperature trend the year 2015 is.
Starting in December 2014, we have completed 7 different “3 month blocks”. If you go into the historic temperature record…the top 7 “3 month blocks” of time in temperature have all been recorded in the last 8 months. The only reason July and August aren’t on there right now? You can’t make a 3 month block of records starting in July and August. The only 2 blocks of time on the chart not from this year come from 2010, the last year there was an El Niño event.
This chart, although not that picturesque, did for me a spectacular job of showing how far above the temperature average 2015 is.
-JBB
Image credit: NOAA Monthly Temperature Update http://www.ncdc.noaa.gov/sotc/global/2015/8/supplemental/page-2 https://twitter.com/EricHolthaus/status/644605733531742209
Earth’s atmosphere is an amazing thing, when you think about it. Without our atmosphere life would be unsustainable here on Earth; but what exactly is it?
The atmosphere is simply a layered mixture of gases, mainly nitrogen (78%), Oxygen (21%) and a mixture of argon, water vapour, carbon dioxide, methane and trace gases. These combined create not only the air we breathe, but also help serve as a sun screen, a temperature regulator and of course protect us from asteroid impacts (most of the time!).
The innermost layer of our atmosphere, and probably the most familiar to us, is the troposphere. Here and up until around 15km from the surface is where the majority of our planets weather systems reside and is where nearly 80% of the Earth’s air is located. The name “troposphere” comes from a Greek word that refers to mixing and this is exactly what happens within the troposphere, as warm air rises to form clouds, rain falls, and winds stir the lands below.
Past the troposphere we discover the stratosphere; a less dense region of the atmosphere which extends out to around 50km. Here, the oxygen molecules are transformed into ozone which forms a protective layer against harmful ultraviolet light from the sun- the importance of this layer has been made evident in our lifetimes; without which, skin cancer rates would be undoubtedly higher. Seeing as ultraviolet energy is being absorbed in this region, the stratosphere has quite extravagant differentials in temperature. At the base of the stratosphere it is extremely cold, around -80 degrees Celsius, at its top, the temperature rises to nearly 0 degrees Celsius.
After the stratosphere comes the mesosphere and here is where a lot of action happens. Any meteors which enter our atmosphere tend to be destroyed in the mesosphere; they “burn up” and never reach the Earth’s surface. This layer, which extends to 85 kilometres from the surface, is one of the fundamental reasons why Earth isn’t covered in meteor craters- if the moon had a mesosphere it would be a much smoother surface.
Next comes the ionosphere- named for the ions created within this layer from energetic particles of sunlight and space. The ionosphere allows for the transmission of radio signals which are invaluable, particularly before the days of satellite communication. Here is also were the auroras are created and who doesn’t love them, eh? The International Space Station has also made its home in the ionosphere.
Lastly, we have the exosphere. This tenuous portion of the Earth's atmosphere extends outward until it interacts with the solar wind. Solar storms compress the exosphere. When the Sun is tranquil, the layer can extend further outward. The reach of this layer varies between 1,000 and 10,000 kilometres, where it merges with interplanetary space.
Together, all these layers make our atmosphere which, sadly, is continually menaced by human activity. Between rising carbon dioxide levels and air pollution, ozone destruction and acid rain, we have divorced our relationship with our environment. It is important not to forget the delicacy which is life here on Earth, we should aim to maintain a mutually beneficial relationship with what has supported our time here on this lovely blue planet. After all, if the relationship is irreconcilable, the environment will get the house... !
Some further information and reading for you:
http://www.ucar.edu/learn/1_1_1.htm
http://www.atmos.illinois.edu/earths_atmosphere/earth_atmosphere.html
Photo was taken from the ISS (credit: NASA/SPL)
Champagne Pool
This geothermal pool is located on New Zealand’s North Island. The hot spring below the pool has temperatures of up to 260°C; however, the pool’s water varies in between 69-74°C. The pool holds its name due to the carbon dioxide content of the water which creates small bubbles (like the ones seen in a glass of champagne). The orange ring around the pool in the image occurs due to deposits of metalloids (a substance with a mixture of properties of both metals and non-metals) in the water such as stibnite. The water from the champagne Pool also feeds the Artist's Palette. The Artist's Palette is another geothermal pool; however, the water in this pool has a yellow tinge due to sulphur deposition.
~SA
http://bit.ly/1UfYaGw by Christian Mehlführer
Lake Kivu: Making the Most of a Deadly Situation
There are a lot of ways a volcano can kill you. Explosions, pyroclastic flows, ash that disrupts climate and growing patterns….and if you needed to add another to the list: exploding lakes. It sounds pretty dire, but some brilliant people with a knack for finding silver linings have come up with a way to turn one of these killers—exploding lakes—into an energy source.
Lakes that sit near volcanoes can become saturated with carbon dioxide. The carbon dioxide collects at the bottom of the lake, and with the right trigger, is suddenly released in a dense cloud, asphyxiating most life in its path. Two of the most infamous of these eruptions both occurred in Cameroon just two years apart—Lake Monoun in 1984 and Lake Nyos in 1986(http://on.fb.me/17hOLeB).
These “limnic eruptions” were very mysterious at first—they were killers that hardly left a trace. Once scientists figured out what was going on, they realized exploding lakes could be quelled by releasing the carbon dioxide slowly (via pipes) instead of letting it build up.
Enter some scientists who realized they could make the most of an unfortunate situation. There is another African lake that is very saturated with gas and shows signs of prehistoric eruptions—Lake Kivu on the border of the Democratic Republic of Congo and Rwanda. Lake Kivu is much larger than both Lake Monoun and Lake Nyos, and it is believed to hold much more gas—except most of this gas is not carbon dioxide, it is methane. Methane is an energy source. Methane can fuel power plants. Methane can provide electricity to the millions of people who live around the banks of Lake Kivu.
The Rwandan government decided to take advantage of this. Working with the energy firm, Contour Global, the aptly named project KivuWatt is under works to convert the methane to electricity. The plan is to suck gas out of the lake, as they would ordinarily do for safety reasons, and then harness the methane in a power plant off the coast.
Rwanda lacks many of its own natural resources and relies on foreign sources of fuel, so KivuWatt has the potential to change things. The first operations are supposed to start later this year.
-CM
For more information: http://bbc.in/1zMEH83 http://bit.ly/170FG9O http://bit.ly/1vFo5zo
Photo credit: The Advocacy Project http://bit.ly/1vNtkgx
