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Russia Fires, Pakistan Floods Linked? Extreme weather driven partly by global warming, experts say.

A family leaves flooded Baseera, Pakistan, this week.
They're raging a continent apart, but two deadly natural disasters—the Russian wildfires and the Pakistan floods—may be connected by the Asian monsoon, one of the most powerful atmospheric forces on the planet, scientists say.
That's because the monsoon—a seasonal wind system that brings rain and floods to Pakistan and much of the rest of Asia in summer—also drives the circulation of air as far away as Europe, said Kevin Trenberth, a senior scientist at the Boulder, Colorado-based National Center for Atmospheric Research.
Air pumped into the upper atmosphere by monsoon winds has to come down somewhere. And with the monsoon's giant reach, much of that air seems to be settling over Russia, where it's creating high-pressure conditions, which favor heat waves, Trenberth said. Near high-pressure systems, air tends to sink, which discourages clouds from forming.
Such circulation patterns are normal, but they're also being enhanced by rising sea temperatures due in part to global warming, he added.
For instance, the northern Indian Ocean has warmed 2 degrees Fahrenheit (1.1 degrees Celsius) since the 1970s. Warmer water releases more moisture into the air, which can supercharge monsoon rains.
"The key message is that it's not just natural variability and not just global warming" but a combination of both, Trenberth said. For instance, the last months of a recent El Niño—a cyclical warming of tropical waters in the central and eastern Pacific Ocean—likely contributed to the high sea temperatures in the Indian Ocean.
He also cautioned that the monsoon link between the Russia fires and Pakistan floods is difficult to prove, since it's based on observations and interpretations of past research.
Fires, Floods, Heat: Record-Breaking Extremes in 2010
This year's fierce monsoon rains have spawned Pakistan's worst flooding in 80 years, affecting nearly 14 million people, according to the New York Times.
And in Russia, widespread fires are stoked by the worst heat wave in Russian memory. Around Moscow, choked with fire-related smog, temperatures have hovered around 100 degrees Fahrenheit (38 degrees Celsius) for weeks and show no sign of letting up soon, according to the Bloomberg news agency.
Trapping the smoke are anticyclones, atmospheric high-pressure centers that occur when monsoon winds form a stable layer of air a few thousand feet above Earth's surface.
Both Russia and Pakistan are also experiencing "remarkable" temperatures in 2010, which is shaping up to be one of the hottest years since record-keeping began in the late 1880s, Jeff Masters, director of meteorology for the Weather Underground website, told National Geographic News in July.
Nine countries have shattered heat records, including Pakistan, which on May 26 logged a mercury reading of 128.3 degrees Fahrenheit (53.5 degrees Celsius)—the highest ever seen in Asia, Masters said.
Extreme events such as heat waves, drought, and monsoon floods are believed by some scientists to be increasing with global warming, and the disasters in Russia and Pakistan may be indications of this, Rosanne D'Arrigo, a research professor at Columbia University's Lamont-Doherty Earth Observatory, said in an email. (See a world map of potential global warming impacts.)
However, D'Arrigo said, it's not possible to ascribe any one event to global warming.
Atmospheric "Logjam" Prolonging Russia Fires, Pakistan Floods
D'Arrigo added that there's a "possible relationship" between the monsoon and the fires—for instance, the Asian monsoon has been linked before in various ways to higher-latitude conditions, such as in the North Atlantic, she said.

Deke Arndt, head of the Climate Monitoring Branch of the U.S. National Oceanic and Atmospheric Administration's National Climatic Data Center, agreed it's likely that the fires can be traced back to the monsoon.
He noted that the events may also be prolonged by an atmospheric "logjam" that's common in the summer but which has been unusually "stubborn and long-lasting" this year.
The blockage occurs when atmospheric winds lock climate phenomena—such as large storms or heat waves—into place for a long period of time. In the United States in the summer, for example, storms will "squat on a place and sit and spin for a week," Arndt said.
"These features, while they're strong, are also really persistent," he said. They "show up [as] day after day of rainfall in India and Pakistan ... and day after day of oppressive conditions in western Russia."
Overall, scientists often struggle to quantify how the climate fits in with such natural occurrences, Arndt said.
But the likely link between the Russian fires and the Pakistan floods "is a great example that things that happen in the atmosphere don't occur in isolation."

Engineers Tap Algae Cell for Electricity

With the help of photosynthesis plants convert light energy to chemical energy. This chemical energy is stored in the bonds of sugars they use for food. Photosynthesis happens inside a chloroplast. Chloroplasts are considered as the cellular powerhouses that make sugars and impart leaves and algae a green hue. During photosynthesis water is split into oxygen, protons and electrons. When sunrays fall on the leaves and reach the chloroplast, electrons get excited and attain higher energy level. These excited electrons are caught by proteins. The electrons are passed through a series of proteins. These proteins utilize more of the electrons’ energy to synthesize sugars until the entire electron’s energy is exhausted.

Now researchers at Stanford are inspired by a new idea. They intercepted the electrons just after they had been excited by light and were at their highest energy levels. They put the gold electrodes inside the chloroplasts of algae cells, and tapped the electrons to create a tiny electrical current. It may be the beginning of the production of “high efficiency” bioelectricity. This will be a clean and green source of energy but minus carbon dioxide.

Stanford University researchers got their work published in the journal Nano Letters (March, 2010). WonHyoung Ryu is the main author of this work. He says, “We believe we are the first to extract electrons out of living plant cells.” The Stanford research team created an exclusive, ultra-sharp gold nanoelectrode for this project.

They inserted the electrodes inside the algal cell membranes. The cell remains alive throughout the whole process. When cells start the photosynthesis, the electrodes attract electrons and produce tiny electric current. Ryu tells us, “We’re still in the scientific stages of the research. We were dealing with single cells to prove we can harvest the electrons.” The byproducts of such electricity production are protons and oxygen. Ryu says, “This is potentially one of the cleanest energy sources for energy generation. But the question is, is it economically feasible?”

Ryu himself provides the answer. He explained that they were able to extract just one picoampere from each cell. This quantity is so little that they would require a trillion cells photosynthesizing for one hour just to get the same amount of energy in a AA battery.

Another drawback of such an experiment is that the cells die after an hour. It might be the small trickles in the membrane around the electrode could be killing the cells. Or cells may be dying because they’re not storing the energy for their own vital functions necessary to sustain life. To attain commercial viability researchers have to overcome these hurdles.

They should go for a plant with larger chloroplasts for a larger collecting area. For such experiment they will also need a bigger electrode that could tap more electrons. With a longer-surviving plant and superior collecting ability, they could harness more electricity in terms of power.

Carbon-based Solar Cells

Solar panels need silicon for absorption of light. Silicon doesn’t come cheap.This cost-factor is preventing people from using solar energy on a large scale. Scientists utilize another substance i.e. ruthenium for solar cells. Rutheniumcan is cheaper than silicon but ruthenium is a rare metal on Earth. It is as rare as platinum. Naturally it can’t be available for mass production. Compared to silicon, carbon is cheap and abundant. The graphene, another form of carbon, is capable of absorbing a wide range of light frequencies.

Graphene is a single sheet of carbon, one atom thick. Graphene has potential to be utilized as an effective, less toxic and cheaper than other alternatives for solar cells. Chemists at Indiana University Bloomington are trying to come up with a better alternative than silicon. If successful, this can be a path breaking discovery.

Other people too took this initiative of using carbon sheets for solar power. But they encountered some hurdles. They used the graphene form of carbon for solar cells. Grephene is akin to graphite used in pencil lead. Graphene absorbs a wide range of light frequencies. Scientists have found large sheets of graphene to be too unmanageable to work with. Large sheets are sticky and get attached with other sheets. Now Indiana University Bloomington researchers are trying to deal with this problem. They are trying to develop non-sticky graphene sheets that are stable. They are putting their efforts on “attaching a semi-rigid, semi-flexible, three-dimensional sidegroup to the sides of the graphene.” They know how to derive energy from carbon. Now chemists from Indiana University Bloomington are graduating to the next logical step i.e. conversion of that energy into electricity. If everything will turn out alright then carbon can be an alternative to expensive silicon and ruthenium, which is as rare as platinum.

Chemists and engineers kept on trying to work out a solution for the stickiness of graphene. They devised many methods for keeping single graphene sheets separate. Till now the most effective solution prior to the Indiana University Bloomington scientists’ experiment has been breaking up graphite (top-down) into sheets and wrap polymers around them. But this method has its own disadvantage. Those graphene sheets are too large for light absorption for solar cells. Indiana University chemists devised a completely new method for carbon sheets. They utilized a 3-D bramble patch between the carbon sheets. This method helped the scientists to dissolve sheets containing as many as 168 carbon atoms. They are successful in making the graphene sheets from smaller molecules (bottom-up) so that they are uniform in size. Till now, it is the biggest stable graphene sheet ever made with the bottom-up approach.

Solar panels need silicon for absorption of light. Silicon doesn’t come cheap.This cost-factor is preventing people from using solar energy on a large scale. Scientists utilize another substance i.e. ruthenium for solar cells. Rutheniumcan is cheaper than silicon but ruthenium is a rare metal on Earth. It is as rare as platinum. Naturally it can’t be available for mass production. Compared to silicon, carbon is cheap and abundant. The graphene, another form of carbon, is capable of absorbing a wide range of light frequencies.

Graphene is a single sheet of carbon, one atom thick. Graphene has potential to be utilized as an effective, less toxic and cheaper than other alternatives for solar cells. Chemists at Indiana University Bloomington are trying to come up with a better alternative than silicon. If successful, this can be a path breaking discovery.

Other people too took this initiative of using carbon sheets for solar power. But they encountered some hurdles. They used the graphene form of carbon for solar cells. Grephene is akin to graphite used in pencil lead. Graphene absorbs a wide range of light frequencies. Scientists have found large sheets of graphene to be too unmanageable to work with. Large sheets are sticky and get attached with other sheets. Now Indiana University Bloomington researchers are trying to deal with this problem. They are trying to develop non-sticky graphene sheets that are stable. They are putting their efforts on “attaching a semi-rigid, semi-flexible, three-dimensional sidegroup to the sides of the graphene.” They know how to derive energy from carbon. Now chemists from Indiana University Bloomington are graduating to the next logical step i.e. conversion of that energy into electricity. If everything will turn out alright then carbon can be an alternative to expensive silicon and ruthenium, which is as rare as platinum.

Chemists and engineers kept on trying to work out a solution for the stickiness of graphene. They devised many methods for keeping single graphene sheets separate. Till now the most effective solution prior to the Indiana University Bloomington scientists’ experiment has been breaking up graphite (top-down) into sheets and wrap polymers around them. But this method has its own disadvantage. Those graphene sheets are too large for light absorption for solar cells. Indiana University chemists devised a completely new method for carbon sheets. They utilized a 3-D bramble patch between the carbon sheets. This method helped the scientists to dissolve sheets containing as many as 168 carbon atoms. They are successful in making the graphene sheets from smaller molecules (bottom-up) so that they are uniform in size. Till now, it is the biggest stable graphene sheet ever made with the bottom-up approach.

What are biofuels? Are all forms of biofuels good?

Biofuels, a form of bioenergy used as transport fuel, can be made from a wide range of plant materials (biomass) such as sugar, wheat, vegetable oils, wood and straws. Those biofuels currently on the market are often made from conventional agricultural crops. They are sometimes referred to as ‘agrofuels’ due to their production from agricultural products.

Biofuels are only one form of energy made from biomass. Other forms of bioenergy, for example biogas, heat and electricity produced from biomass, generally have a higher efficiency with less associated environmental concerns compared with biofuels. If managed sustainably, bioenergy from renewable sources has its merits and is key to tackle global climate change.

Andy Hay (rspb-images.com) Rapeseed is a major feedstock to make biodiesel in Europe Zoom In | Hi-Res

First-generation biofuels

Current biofuels are often called ‘first generation biofuels’ because they are made with relatively simple technologies. Bioethanol can be produced from any feedstocks that contain a high starch or sugar content such as corn (maize), wheat, sugarcane, and sugar beet. After fermentation and distillation, this bioethanol can be mixed with petrol/gasoline in various proportions for car use. Biodiesel, on the other hand, is made through transesterification of vegetable oil such as palm oil, rapeseed oil, soya bean oil and even used-cooking oil.

Even though such biofuels are made from plant material and hence are a renewable source, they are not as ‘green’ as they seem. To produce biofuels, large amount of land is need to cultivate the crop, together with irrigation, use of fertilizers, transportation, conversion and refinery processes, all these require energy input and emit carbon dioxide. There are a large and growing number of studies that suggest that the use of current biofuels would save very little greenhouse gas, destroy wildlife habitats, as well as affect indigenous and rural poor communities around the world. (more on their Impacts)

Second-generation bio fuels

Due to the generally lower carbon emission and the greater possibility to use waste material, there are high hopes for so-called ‘second generation bio fuels’, which are mainly made from non-edible feed stocks as lignocellulosic materials like wood and straw. However, the cost of converting such biomass into bio ethanol or bio diesel or other types of transport fuels is still very high, and the technology still remains in the demonstration phase. Technological breakthroughs will be needed to bring the cost down, and depending on the technology it is estimated that second generation bio fuels will not become fully commercial for several years to come and will need of significant government support (IEA 2008). There are also uncertainties about their potential to provide transport fuel in a large scale due to the logistical challenge of transporting biomass material to large production facilities (OECD, 2007). Moreover, they have their share of environmental concerns as their production can also involve the requirement of land which can lead to direct and indirect land use change.

It is important to indicate that the terminology of these fuel sources might be misleading, as it suggests that first-generation bio fuels are a necessary first step to second generation or that the first are older than the second. On the contrary second generation bio fuels were firstly developed in 1930 in Germany converting biomass to liquids and for the production of each of these an entire different infrastructure is needed.

Is Global Warming Real?

Snow-mantled crags frame the severe beauty of Queen Maud Land in central Antarctica.

In recent years, global warming has been the subject of a great deal of political controversy. As scientific knowledge has grown, this debate is moving away from whether humans are causing warming and toward questions of how best to respond.

Signs that the Earth is warming are recorded all over the globe. The easiest way to see increasing temperatures is through the thermometer records kept over the past century and a half. Around the world, the Earth's average temperature has risen more than 1 degree Fahrenheit (0.8 degrees Celsius) over the last century, and about twice that in parts of the Arctic.

This doesn’t mean that temperatures haven't fluctuated among regions of the globe or between seasons and times of day. But if you average out the temperature all over the world over the course of a year, you see that temperatures have been creeping upward.

Although we can't look at thermometers going back thousands of years, we do have some records that help us figure out what temperatures and concentrations were like in the distant past. For example, trees store information about the climate in the place where they live. Each year, trees grow thicker and form new rings. In warmer and wetter years, the rings are thicker. Old trees and wood can tell us about conditions hundreds or even several thousands of years ago.

Keys to the past are also buried under lakes and oceans. Pollen, creatures, and particles fall to the bottom of oceans and lakes each year, forming sediments. Sediments preserve all these bits and pieces, which contain a wealth of information about what was in the air and water when they fell. Scientists reveal this record by inserting hollow tubes into the mud to collect sediment layers going back millions of years.

For a direct look at the atmosphere of the past, scientists drill cores through the Earth's polar ice sheets. Tiny bubbles trapped in the gas are actually pieces of the Earth's past atmosphere, frozen in time. That's how we know that the concentrations of greenhouse gases since the industrial revolution are higher than they've been for hundreds of thousands of years.

Computer models help scientists to understand the Earth's climate, or long-term weather patterns. Models also allow scientists to make predictions about the future climate. Basically, models simulate how the atmosphere and oceans absorb energy from the sun and transport it around the globe. Factors that affect the amount of the sun's energy reaching Earth's surface are what drive the climate in these models, as in real life. These include things like greenhouse gases, particles in the atmosphere (such as from volcanoes), and changes in energy coming from the sun itself.

Global Warming Solutions What Can We Do?

The evidence that humans are causing global warming is strong, but the question of what to do about it remains controversial. Economics, sociology, and politics are all important factors in planning for the future.

Even if we stopped emitting greenhouse gases (GHGs) today, the Earth would still warm by another degree Fahrenheit or so. But what we do from today forward makes a big difference. Depending on our choices, scientists predict that the Earth could eventually warm by as little as 2.5 degrees or as much as 10 degrees Fahrenheit.

A commonly cited goal is to stabilize GHG concentrations around 450-550 parts per million (ppm), or about twice pre-industrial levels. This is the point at which many believe the most damaging impacts of climate change can be avoided. Current concentrations are about 380 ppm, which means there isn't much time to lose. According to the IPCC, we'd have to reduce GHG emissions by 50% to 80% of what they're on track to be in the next century to reach this level.

Is this possible?

Many people and governments are already working hard to cut greenhouse gases, and everyone can help.

Researchers Stephen Pacala and Robert Socolow at Princeton University have suggested one approach that they call "stabilization wedges." This means reducing GHG emissions from a variety of sources with technologies available in the next few decades, rather than relying on an enormous change in a single area. They suggest 7 wedges that could each reduce emissions, and all of them together could hold emissions at approximately current levels for the next 50 years, putting us on a potential path to stabilize around 500 ppm.

There are many possible wedges, including

1.Improvements to energy efficiency and vehicle fuel economy (so less energy has to be produced), and

2.increases in wind and solar power,

3.hydrogen produced from renewable sources,

4.bio fuels (produced from crops),

5.natural gas, and

6.nuclear power.

7.There is also the potential to capture the carbon dioxide emitted from fossil fuels and store it underground—a process called "carbon sequestration."

In addition to reducing the gases we emit to the atmosphere, we can also increase the amount of gases we take out of the atmosphere. Plants and trees absorb CO2 as they grow, "sequestering" carbon naturally. Increasing forestlands and making changes to the way we farm could increase the amount of carbon we're storing.

Some of these technologies have drawbacks, and different communities will make different decisions about how to power their lives, but the good news is that there are a variety of options to put us on a path toward a stable climate.

Electricity from Biomass

The term "biomass" encompasses diverse fuels derived from timber, agriculture and food processing wastes or from fuel crops that are specifically grown or reserved for electricity generation. Biomass fuel can also include sewage sludge and animal manure. Some biomass fuels are derived from trees. Given the capacity of trees to regenerate, these fuels are considered renewable. Burning crop residues, sewage or manure - all wastes that are continually generated by society -- to generate electricity may offer environmental benefits in the form of preserving precious landfill space OR may be grown and harvested in ways that cause environmental harm.

At present, most biomass power plants burn lumber, agricultural or construction/demolition wood wastes. Direct Combustion power plants burn the biomass fuel directly in boilers that supply steam for the same kind of steam-electric generators used to burn fossil fuels. With biomass gasification, biomass is converted into a gas - methane - that can then fuel steam generators, combustion turbines, combined cycle technologies or fuel cells. The primary benefit of biomass gasification, compared to direct combustion, is that extracted gasses can be used in a variety of power plant configurations.

In terms of capacity, biomass power plants represent the second largest amount of renewable energy in the nation.

Because biomass technologies use combustion processes to produce electricity, they can generate electricity at any time, unlike wind and most solar technologies, which only produce when the wind is blowing or sun is shining. Biomass power plants currently represent 11,000 MW - the second largest amount of renewable energy in the nation.

What are the environmental impacts?

Whether combusting directly or engaged in gasification, biomass resources do generate air emissions. These emissions vary depending upon the precise fuel and technology used. If wood is the primary biomass resource, very little SO2 comes out of the stack. NOx emissions vary significantly among combustion facilities depending on their design and controls. Some biomass power plants show a relatively high NOx emission rate per kilowatt hour generated if compared to other combustion technologies.

This high NOx rate, an effect of the high nitrogen content of many biomass fuels, is one of the top air quality concerns associated with biomass.

Carbon monoxide (CO) is also emitted - sometimes at levels higher than those for coal plants.

Biomass plants also release carbon dioxide (CO2), the primary greenhouse gas. However, the cycle of growing, processing and burning biomass recycles CO2 from the atmosphere. If this cycle is sustained, there is little or no net gain in atmospheric CO2. Given that short rotation woody crops (i.e., fast growing woody plant types) can be planted, matured and harvested in shorter periods of time than natural growth forests, the managed production of biomass fuels may recycle CO2 in one-third less time than natural processes.

Biomass power plants also divert wood waste from landfills, which reduces the productions and atmospheric release of methane, another potent greenhouse gas.

Another air quality concern associated with biomass plants is particulates. These emissions can be readily controlled through conventional technologies. To date, no biomass facilities have installed advanced particulate emission controls. Still, most particulate emissions are relatively large in size. Their impacts upon human health remain unclear.

The collection of biomass fuels can have significant environmental impacts. Harvesting timber and growing agricultural products for fuel requires large volumes to be collected, transported, processed and stored. Biomass fuels may be obtained from supplies of clean, uncontaminated wood that otherwise would be landfilled or from sustainable harvests. In both of these fuel collection examples, the net environmental plusses of biomass are significant when compared to fossil fuel collection alternatives. On the other hand, the collection, processing and combustion of biomass fuels may cause environmental problems if, for example, the fuel source contains toxic contaminants, agricultural waste handling pollutes local water resources, or burning biomass deprives local ecosystems of nutrients that forest or agricultural waste may otherwise provide.

volcanoes

Volcanoes are awesome manifestations of the fiery power contained deep within the Earth. These formations are essentially vents on the Earth's surface where molten rock, debris, and gases from the planet's interior are emitted.

When thick magma and large amounts of gas build up under the surface, eruptions can be explosive, expelling lava, rocks and ash into the air. Less gas and more viscous magma usually mean a less dramatic eruption, often causing streams of lava to ooze from the vent.

The mountain-like mounds that we associate with volcanoes are what remain after the material spewed during eruptions has collected and hardened around the vent. This can happen over a period of weeks or many millions of years.

A large eruption can be extremely dangerous for people living near a volcano. Flows of searing lava, which can reach 2,000 degrees Fahrenheit (1,250 degrees Celsius) or more, can be released, burning everything in its path, including whole towns. Boulders of hardening lava can rain down on villages. Mud flows from rapidly melting snow can strip mountains and valleys bare and bury towns. Ash and toxic gases can cause lung damage and other problems, particularly for infants and the elderly. Scientists estimate that more than 260,000 people have died in the past 300 years from volcanic eruptions and their aftermath.

Volcanoes tend to exist along the edges between tectonic plates, massive rock slabs that make up Earth's surface. About 90 percent of all volcanoes exist within the Ring of Fire along the edges of the Pacific Ocean.

About 1,900 volcanoes on Earth are considered active, meaning they show some level of activity and are likely to explode again. Many other volcanoes are dormant, showing no current signs of exploding but likely to become active at some point in the future. Others are considered extinct.