The idea that a changing climate can persuade the ground to shake, volcanoes to rumble, and tsunamis to crash on to unsuspecting coastlines seems, at first, to be bordering on the insane. How can what happens in the thin envelope of gas that shrouds and protects our world possibly influence the potentially earth-shattering processes that operate deep beneath the surface? The fact that it does reflects a failure of our imagination and a limited understanding of the manner in which the different physical components of our planet—the atmosphere, the oceans, and the solid earth, or geosphere—intertwine and interact.
If we think about climate change at all, most of us do so in a very simplistic way: the weather might get a bit warmer, floods and droughts may become more of a problem, and sea levels will slowly creep upwards. Evidence reveals, however, that our planet is an almost unimaginably complicated beast, which reacts to a dramatically changing climate in all manner of different ways, a few straightforward and predictable, some surprising, and others downright implausible. Into the latter category fall the manifold responses of the geosphere.
The world we inhabit has an outer rind that is extraordinarily sensitive to change. While the earth's crust may seem safe and secure, the geological calamities that happen with alarming regularity confirm that this is not the case. Here in the United Kingdom, we only have to go back a couple years to April 2010, when the word on everyone's lips was Eyjafjallajökull—the ice-covered Icelandic volcano that brought UK and European air traffic to a grinding halt. Less than a year ago, our planet's ability to shock and awe headed the news once again as the east coast of Japan was bludgeoned by a cataclysmic combination of megaquake and tsunami, resulting—at a quarter of a trillion dollars or so—in the biggest natural-catastrophe bill ever.
In the light of such events, it somehow seems appropriate to imagine the earth beneath our feet as a slumbering giant that tosses and turns periodically in response to various pokes and prods. Mostly, these are supplied by the stresses and strains associated with the eternal dance of a dozen or so rocky tectonic plates across the face of our world, a sedate waltz that proceeds at about the speed that fingernails grow. Changes in the environment too, however, have a key role to play in waking the giant, as growing numbers of geological studies targeting our post-ice-age world have disclosed.
Between about 20,000 and 5,000 years ago, our planet underwent an astonishing climatic transformation. Over the course of this period, it flipped from the frigid wasteland of deepest and darkest ice age to the—broadly speaking—balmy, temperate world upon which our civilization has developed and thrived. During this extraordinarily dynamic episode, as the immense ice sheets melted and colossal volumes of water were decanted back into the oceans, the pressures acting on the solid earth also underwent massive change. In response, the crust bounced and bent, rocking our planet with a resurgence in volcanic activity, a proliferation of seismic shocks and burgeoning giant landslides.
The most spectacular geological effects were reserved for high latitudes. Here, the crust across much of northern Europe and North America had been forced down by hundreds of meters and held at bay for tens of thousands of years beneath the weight of sheets of ice 20 times thicker than the height of the London Eye. As the ice dissipated in soaring temperatures, the crust popped back up like a coiled spring released, at the same time tearing open major faults and triggering great earthquakes in places where they are unheard of today. Even now, the crust underpinning those parts of Europe and North America formerly imprisoned beneath the great continental ice sheets continues to rise—albeit at a far more sedate rate.
As last year's events in Japan most ably demonstrated, when the ground shakes violently beneath the sea, a tsunami may not be far behind. These unstoppable walls of water are hardly a surprise when they happen within the so-called ring of fire that encompasses the Pacific basin, but in the more tectonically benign North Atlantic their manifestation could reasonably be regarded as a bit of a shock. Nonetheless, there is plenty of good, hard evidence that this was the case during post-glacial times. Trapped within the thick layers of peat that pass for soil on Shetland—the UK's northernmost outpost—are intrusions of sand that testify to the inland penetration of three tsunamis during the last 10,000 years.
Volcanic blasts too can be added to the portfolio of postglacial geological pandemonium, the warming climate being greeted by an unprecedented fiery outburst that wracked Iceland as its frozen carapace dwindled, and against which the recent ashy ejaculation from the island's most unpronounceable volcano pales.
The huge environmental changes that accompanied the rapid post-glacial warming of our world were not confined to the top and bottom of the planet. All that meltwater had to go somewhere, and as the ice sheets dwindled, so the oceans grew. An astounding 52 million cubic kilometers of water was sucked from the oceans to form the ice sheets, causing sea levels to plummet by about 130 meters—the height of the Wembley Stadium arch. As the ice sheets melted so this gigantic volume of water was returned, bending the crust around the margins of the ocean basins under the enormous added weight, and provoking volcanoes in the vicinity to erupt and faults to rupture, bringing geological mayhem to regions remote from the ice's polar fastnesses.
The breathtaking response of the geosphere as the great ice sheets crumbled might be considered as providing little more than an intriguing insight into the prehistoric workings of our world, were it not for the fact that our planet is once again in the throes an extraordinary climatic transformation—this time brought about by human activities. Clearly, the earth of the early 21st century bears little resemblance to the frozen world of 20,000 years ago. Today, there are no great continental ice sheets to dispose of, while the ocean basins are already pretty much topped up. On the other hand, climate change projections repeatedly support the thesis that global average temperatures could rise at least as rapidly in the course of the next century or so as during post-glacial times, reaching levels at high latitudes capable of driving catastrophic breakup of polar ice sheets as thick as those that once covered much of Europe and North America. Could it be then, that if we continue to allow greenhouse gas emissions to rise unchecked and fuel serious warming, our planet's crust will begin to toss and turn once again?
The signs are that this is already happening. In the detached US state of Alaska, where climate change has propelled temperatures upward by more than 3 degrees Celsius in the last half century, the glaciers are melting at a staggering rate, some losing up to 1 kilometer in thickness in the last 100 years. The reduction in weight on the crust beneath is allowing faults contained therein to slide more easily, promoting increased earthquake activity in recent decades. The permafrost that helps hold the state's mountain peaks together is also thawing rapidly, leading to a rise in the number of giant rock and ice avalanches. In fact, in mountainous areas around the world, landslide activity is on the up, a reaction both to a general ramping-up of global temperatures and to the increasingly frequent summer heat waves.
Whether or not Alaska proves to be the "canary in the cage"—the geological shenanigans there heralding far worse to come—depends largely upon the degree to which we are successful in reducing the ballooning greenhouse gas burden arising from our civilization's increasingly polluting activities, thereby keeping rising global temperatures to a couple of degrees centigrade at most. So far, it has to be said, there is little cause for optimism with emissions rocketing by almost 6 percent in 2010 when the world economy continued to bump along the bottom. Furthermore, the failure to make any real progress on emissions control at last December's Durban climate conference ensures that the outlook is bleak. Our response to accelerating climate change continues to be consistently asymmetric, in the sense that it is far below the level that the science says is needed if we are to have any chance of avoiding the all-pervasive devastating consequences.
So what—geologically speaking—can we look forward to if we continue to pump out greenhouse gases at the current hell-for-leather rate? With resulting global average temperatures likely to be several degrees higher by this century's end, we could almost certainly say an eventual goodbye to the Greenland ice sheet, and probably that covering West Antarctica too, committing us—ultimately—to a 10-meter or more hike in sea levels.
GPS measurements reveal that the crust beneath the Greenland ice sheet is already rebounding in response to rapid melting, providing the potential—according to researchers—for future earthquakes, as faults beneath the ice are relieved of their confining load. The possibility exists that these could trigger submarine landslides spawning tsunamis capable of threatening North Atlantic coastlines. Eastern Iceland is bouncing back too as its Vatnajökull ice cap fades away. When and if it vanishes entirely, new research predicts a lively response from the volcanoes currently residing beneath. A dramatic elevation in landslide activity would be inevitable in the Andes, Himalayas, European Alps, and elsewhere, as the ice and permafrost that sustains many mountain faces melts and thaws.
Across the world, as sea levels climb remorselessly, the load-related bending of the crust around the margins of the ocean basins might—in time—act to sufficiently "unclamp" coastal faults such as California's San Andreas, allowing them to move more easily, at the same time acting to squeeze magma out of susceptible volcanoes that are primed and ready to blow.
The bottom line is that through our climate-changing activities we are loading the dice in favor of escalating geological havoc at a time when we can most do without it. Unless there is a dramatic and completely unexpected turnaround in the way in which the human race manages itself and the planet, then long-term prospects for our civilization look increasingly grim. At a time when an additional 220,000 people are lining up at the global soup kitchen each and every night, when energy, water, and food resources are coming under ever-growing pressure, and when the debilitating effects of anthropogenic climate change are insinuating themselves increasingly into every nook and cranny of our world and our lives, the last thing we need is for the dozing subterranean giant to awaken. THANKS KAINAT MUNIBA KHAN
Researchers at the University of Wisconsin, Madison, exposed human skin cells to the smog-related ozone in the laboratory and found that they turned on cellular machinery that normally responds to stress, suggesting ozone may be toxic to human skin. However, further experiments are required to confirm the findings in people.
BEFORE A FLOOD (WHEN FLOODING IS FORECAST)
Be alert.
Monitor your surroundings.
Monitor NOAA Weather Radio, local television and radio stations, or go to www.weather.gov.
If a flash flood warning is issued for your area: Climb to safety immediately.
Flash floods develop quickly. Do not wait until you see rising water.
Get out of low areas subject to flooding.
If driving, do not drive through flooded roadways!
Assemble disaster supplies:
Drinking water – Fill clean containers.
Food that requires no refrigeration or cooking.
Cash.
Medications and first aid supplies.
Clothing, toiletries.
Battery-powered radio.
Flashlights.
Extra batteries.
Important documents: insurance papers, medical records, bank account numbers.
Be prepared to evacuate.
Identify places to go.
Identify alternative travel routes that are not prone to flooding.
Plan what to do with your pets.
Fill your car’s gas tank.
If told to leave, do so quickly.
Review your Family Disaster Plan.
Discuss flood plans with your family.
Decide where you will meet if separated.
Designate a contact person who can be reached if family members get separated. Make sure every family member has the contact information.
Protect your property.
Move valuables and furniture to higher levels.
Move hazardous materials (such as paint, oil, pesticides, and cleaning supplies) to higher locations.
Disconnect electrical appliances. Do not touch them if you are wet or standing in water.
Bring outside possessions indoors or tie them down securely. This includes lawn furniture, garbage cans, and other movable objects.
Seal vents to basements to prevent flooding.
DURING A FLOOD
Be alert.
Monitor your surroundings.
Monitor NOAA Weather Radio, local television and radio stations, or go to www.weather.gov.
Don’t drive unless you have to.
If you must drive, travel with care.
Make sure your vehicle has enough fuel.
Follow recommended routes. DO NOT sightsee.
Avoid disaster areas. Your presence might hamper rescue or other emergency operations and put you at further risk.
Watch for washed out roads, earth slides, and downed trees or power lines.
Be especially cautious at night, when it is harder to recognize flood dangers.
If the vehicle stalls, abandon it.
If water rises around your car, leave the vehicle immediately. Climb to higher ground as quickly as possible.
NEVER drive through flooded roadways. STOP! Turn Around Don’t Drown.
The roadbed may be washed out.
You can lose control of your vehicle in only a few inches of water.
Your car may float. Vehicles can be swept away by less than 2 feet of water.
Do not drive around a barricade. Turn around and go another way!
Get to high ground – Climb to safety!
Get out of low areas that may be subject to flooding.
Avoid already-flooded areas and do not attempt to cross flowing water.
Stay away from power lines and electrical wires.
Evacuate immediately, if you think you are at risk or are advised to do so!
Act quickly. Save yourself, not your belongings.
Move to a safe area before access is cut off by rising water.
Families should use only one vehicle to avoid getting separated and reduce traffic jams.
Shut off water, gas, and electrical services before leaving.
Secure your home: lock all doors and windows.
If directed to a specific location, go there.
Never try to walk or swim through flowing water.
If flowing water is above your ankles, STOP! Turn around and go another way.
If it is moving swiftly, water 6 inches deep can knock you off your feet.
Be aware that people have been swept away wading through flood waters.
NEVER allow children to play around high water, storm drains, creeks, or rivers.
Shut off the electricity at the circuit breakers.
If someone falls in or is trapped in flood water:
Do not go after the victim!
Use a floatation device. If possible throw the victim something to help them float, such as a spare tire, large ball, or foam ice chest.
Call 911. Call for assistance and give the correct location information.
AFTER A FLOOD
Wait until it is safe to return.
Monitor NOAA Weather Radio or local television and radio stations.
Do not return to flooded areas until authorities indicate it is safe to do so.
Do not visit disaster areas following a flood. Your presence may hamper urgent emergency response and rescue operations.
Travel with care.
Follow recommended routes. DO NOT sightsee.
Watch for washed out roads, earth slides, and downed trees or power lines.
Stay away from downed power lines.
If a building was flooded, check for safety before entering.
Do not enter a building if it is still flooded or surrounded by floodwater.
Check for structural damage. Inspect foundations for cracks or other damage.
Turn off any outside gas lines at the meter tank.
Do not enter a building that has flooded until local building officials have inspected it for safety.
Use extreme caution when entering buildings.
Wear sturdy shoes. The most common injury following a disaster is cut feet.
Use ONLY battery-powered lighting. Flammable material may be present.
Look for fire hazards (such as damaged gas lines, flooded electrical circuits, or submerged furnaces).
Check for gas leaks. If you smell gas or hear a blowing or hissing noise, open a window and quickly leave the building. If possible turn off the gas at the outside main valve. Call the gas company.
Report broken utility lines to appropriate authorities.
Check for electrical system damage (sparks, broken or frayed wires, or the smell of burning insulation). Turn off the electricity at the main circuit breaker if you can reach it without stepping in water.
Examine walls, floors, doors, windows, and ceilings for risk of collapsing.
Watch out for animals that might have entered with the floodwaters.
Let the building air out to remove foul odors or escaping gas.
Take pictures of the damage, both of the building and its contents, for insurance claims.
Get professional help.
Seek necessary medical care. Do not neglect minor wounds or illnesses.
Food, clothing, shelter, and first aid are available from the American Red Cross.
If the gas has been turned off for any reason, it must be turned back on by a professional.
Have an electrician check the electrical system and appliances.
Wells should be pumped out and the water tested for purity before drinking.
Your home is no longer a safe place.
Throw away medicine, food, or water that had contact with floodwaters (including canned goods).
If water is of questionable purity, boil drinking water for 10 minutes.
Restrict children from playing in flooded areas.
Keep windows and doors open for ventilation.
Pump out flooded basements gradually (removing about 1/3 of the water volume each day) to avoid structural damage.
Keep the power off until an electrician has inspected the system for safety. All electrical equipment should be checked and dried before being returned to service.
Clean and disinfect everything that got wet.
Service damaged sewage systems as soon as possible.
When making repairs, protect your property from future flood damage.
Follow local building codes.
Use flood-resistant materials and techniques.
Elevate electrical components above the potential flood height.
Elevate utilities (washer, dryer, furnace, and water heater) above the level of anticipated flooding.
Consider elevation of the entire structure.
Install a backflow valve in the sewer system.
The reason behind floods is not just natural calamities, but also the sins of mankind. Every living thing on the Earth is the part of an eco-system created by God. There is a natural balance and equilibrium in this eco-system. When an external force interferes with the eco-system of the Earth, its equilibrium is badly shattered. Nature can tolerate external interference to only some extent, after which, terrible consequences are unleashed. These consequences can be seen in different forms. They might be in the form of hot, boiling lava which erupts from terrifying volcanoes, hurricanes, tornadoes, earthquakes or cloud bursts leading to floods. Humans are the only creatures who do not learn a lesson from such natural calamities and keep interfering with the balance of nature. Mankind has been tarnishing the natural beauty for centuries. Even seas and rivers revolt when they are deprived of the land which was once their territory. The increasing human population is forcibly reclaiming seas to accommodate the larger numbers of humans. In Pakistan, there have been floods worse than the floods causing a disaster in the country at present. However, in terms of loss of lives and property, the current flood is the worst one in the history of the country. One of the reasons behind this flood is that populations have settled near the banks of rivers. Due to a long period of draught, the flow and volume of water in River Sindh had greatly reduced. So, people had settled near it. Therefore, these were the first ones to be affected by the floods in that region. The people of the Northern Areas of Pakistan and Khyberpakhtunkhwa had to face the greatest amount of damage and loss. The disastrous flood has consumed entire populations living near the river. During the season of monsoons, Indian opens its spillways causing millions of cusecs of water to be diverted towards Pakistan. As a result, the rivers start overflowing. Moreover, the silt present in rivers and dams causes their apparent water level to rise beyond their capacity, since the silt has already reduced their capacity to hold water. This is another reason that leads to floods. Trees can act as a barrier to the flood water. However, large scale cutting down of huge forests has deprived us of this natural shield. Furthermore, the roots of trees hold the soil. Due to cutting down of these trees, soil starts eroding. This is one of the major reasons why our dams and rivers have become silted. Another reason behind floods is rain water which fails to reach the seas. In India and Pakistan, sewers are not cleaned regularly. Blockages in the sewer systems cause them to start boiling over. During rain season, these sewers flood the nearby regions. Continuous rain is the major reason behind floods. Moreover, increase in global warming causes glaciers to melt which causes the water level of rivers to rise. This is how nearby regions are swallowed up by the disastrous flood water.
