Thursday, October 23, 2008

Health Alerts of Global Warming

Global warming is not only a threat to our future health, it already contributes to more than 150,000 deaths and 5 million illnesses annually. Global warming may affect human health in a surprising number of ways: speeding the spread of infectious diseases such as malaria and dengue fever; creating conditions that lead to potentially fatal malnutrition and diarrhea; and increasing the likelihood of heat waves and floods.

The few studies that have examined the relation between warming and human health or mortality in depth have focused either on increases in the number of days of very hot weather and the resulting mortality or on the spread of infectious diseases by such vectors as mosquitoes, flies, and snails.

According to the scientists, who have mapped the growing health impacts of global warming, the data show that global warming affects different regions in very different ways. Global warming is particularly hard on people in poor countries, which is ironic, because the places that have contributed the least to global warming are most vulnerable to the death and disease higher temperatures can bring.

Scientists believe that greenhouse gases will increase the global average temperature by approximately 6 degrees Fahrenheit by the end of the century. Extreme floods, droughts and heat waves, such as Europe's 2003 heat wave, are likely to strike with increasing frequency. Other factors such as irrigation and deforestation can also affect local temperatures and humidity.

Doctors and scientists around the world are becoming increasingly alarmed over global warming’s impact on human health. Abnormal and extreme weather, which scientists have long predicted would be an early effect of global warming, have claimed hundreds of lives across the US in recent years. Our warming climate is also creating the ideal conditions for the spread of infectious disease, putting millions of people at risk.

Rises in temperature produced by global warming could result in an increase in the number of people being admitted to hospital with kidney disease, heart disease and mental illness in Australian cities. Global warming might also bring a significant increase in previously uncommon diseases such as Dengue and Ross River fever to Australia's rural communities, where temperature increases were expected to be more dramatic.

The effects of global warming on health :
Midwest and Northeast. Major cities such as New York and Chicago could see temperatures that would mean more heat stress and heatstroke. The poor and the elderly would be hit especially hard.
The heat wave in Western Europe in 2003 killed in excess of 30,000 people who wouldn't have died otherwise.
Southwest. Higher temperatures and decreased rain are likely to strain already limited water sources, increasing the likelihood of wildfires and air pollution.
Great Plains. Increased temperatures could mean scorching summers and more mild winters which would significantly hurt food production.

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Friday, September 5, 2008

Chaos and Hysteria of Climate Change

As the estimated cost of measures proposed by politicians to "combat global warming" soars ever higher - such as the International Energy Council's $45 trillion - "fighting climate change" has become the single most expensive item on the world's political agenda.

As Senators Obama and McCain vie with the leaders of the European Union to promise 50, 60, even 80 per cent cuts in "carbon emissions", it is clear that to realise even half their imaginary targets would necessitate a dramatic change in how we all live, and a drastic reduction in living standards.

All this makes it rather important to know just why our politicians have come to believe that global warming is the most serious challenge confronting mankind, and just how reliable is the evidence for the theory on which their policies are based.

Scientists have become more certain that humans are responsible for a large part of global warming. Estimates of temperature increases, heat waves, and cold waves are all nearly identical to those produced six years ago.

From about 1450 to 1850, Earth passed through what is called the Little Ice Age (Some scientists place the start date as early as 1300 and the end date as late as 1890). During this period of renewed cold, alpine glaciers advanced in virtually all the world's mountain areas, and the Arctic islands' ice caps grew larger.nters became colder and summers cooler, though the effect on winters was generally greater. Worldwide, the climate change damaged many ecosystems. Floods, plague, and famine devastated Europe. Crops failed, especially in northern regions. In higher latitudes, great storms increasingly roiled the skies. A storm that hit southern England on December 7-8, 1703, blew down a lighthouse, wrecked houses, tossed ships onto land, and killed 8,000 people. Drought and flood often besieged the same areas.

Global warming will sink major European cities under water and bring about nuclear wars, famine, droughts and global rioting as desperate people search (and fight for) what little food, water and energy remains.

There are ominous signs that the earth's weather patterns have begun to change dramatically and that these changes may portend a drastic decline in food production - with serious political implications for just about every nation on earth. The drop in food production could begin quite soon. The evidence in support of these predictions has now begun to accumulate so massively that meteorologist are hard-pressed to keep up with it.

The continued rapid cooling of the earth since WWII is in accord with the increase in global air pollution associated with industrialization, mechanization, urbanization and exploding population.

Catastrophe and chaos as unguided weapons with which forlornly to threaten society into behavioural change. climate change-induced causes of conflict are likely to be: degradation of freshwaters; decline in food production; increase in storm and flood disasters and environmentally-induced migration.

Climate change is a real and serious problem. But the problem with the recent media frenzy is that some seem to believe no new report or development is enough if it doesn't reveal more serious consequences.

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Wednesday, September 3, 2008

Relation Global Warming and Hurricane

"Temperature increases are taking place all over the world, and that's causing stronger storms," Gore declares. It's a clear and powerful message: Global warming is not just a looming disaster we can palm off on future generations. It's here now, and people are dying because of it.

Many scientists already believed: that the atmosphere, warmed up by mankind's relentless pumping of carbon dioxide into the air, is also warming up the world's prime hurricane breeding grounds. (Tropical sea surface temperatures have risen by about 1 degree Fahrenheit since 1970, but a direct link to the warming atmosphere had not been so clearly established.) A media firm working for one of the study's sponsoring institutions turned the hype up a notch, billing the revelation as "the final piece of the puzzle" connecting an upsurge in powerful hurricanes to global warming.

The hurricane-warming link isn't settled at all. Rather, it's a very contentious debate between two groups of scientists—computer-modeling atmospheric scientists versus meteorologists—who have very different methods, ideas, and priorities. The debate has been raging for months, with attacks and counterattacks—albeit very polite ones—appearing regularly in top scientific journals. Because the issue has massive policy implications and the particulars are difficult to understand and explain, the competing groups have also resorted to dueling press releases and other forms of media outreach.

Given the high degree of interest in the possible relationship between climate change and tropical cyclones (including hurricanes and typhoons).

The strongest hurricanes in the present climate may be upstaged by even more intense hurricanes over the next century as the earth's climate is warmed by increasing levels of greenhouse gases in the atmosphere. Although we cannot say at present whether more or fewer hurricanes will occur in the future with global warming, the hurricanes that do occur near the end of the 21st century are expected to be stronger and have significantly more intense rainfall than under present day climate conditions.

Tropical cyclone wind-speed monitoring has changed dramatically over the last few decades leading to difficulties in determining accurate trends.

Weather events will always result from a combination of deterministic factors (including greenhouse gas forcing or slow natural climate cycles) and stochastic factors (pure chance).

In particular, the available scientific evidence indicates that it is likely that global warming will make - and possibly already is making - those hurricanes that form more destructive than they otherwise would have been.

The basic connection between the two is actually fairly simple: warm water, and the instability in the lower atmosphere that is created by it, is the energy source of hurricanes. This is why they only arise in the tropics and during the season when SSTs are highest (June to November in the tropical North Atlantic).

SST is not the only influence on hurricane formation. Strong shear in atmospheric winds (that is, changes in wind strength and direction with height in the atmosphere above the surface), for example, inhibits development of the highly organized structure that is required for a hurricane to form. In the case of Atlantic hurricanes, the El Nino/Southern Oscillation tends to influence the vertical wind shear, and thus, in turn, the number of hurricanes that tend to form in a given year. Many other features of the process of hurricane development and strengthening, however, are closely linked to SST.

The frequency of the strongest (category 5) hurricanes roughly triples in the anthropogenic climate change scenario relative to the control. This suggests that hurricanes may indeed become more destructive (1) as tropical SSTs warm due to anthropogenic impacts. The frequency of all tropical storms and hurricanes (lumping the weak ones in with the strong ones) rather than a measure of changes in the intensity of the storms.

Trends in the strongest category storms, maximum hurricane winds, and changes in minimum central pressures, suggest a systematic increase in the intensities of those storms that form.

As tropical SSTs have increased in past decades, so has the intrinsic destructive potential of hurricanes.

The key question then becomes this: Why has SST increased in the tropics? Is this increase due to global warming (which is almost certainly in large part due to human impacts on climate)? Or is this increase part of a natural cycle?

So the question to ask here is: why is the Gulf of Mexico so hot at present - how much of this could be attributed to global warming, and how much to natural variability? More detailed analysis of the SST changes in the relevant regions, and comparisons with model predictions, will probably shed more light on this question in the future. At present, however, the available scientific evidence suggests that it would be premature to assert that the recent anomalous behavior can be attributed entirely to a natural cycle. But ultimately the answer to what caused Katrina is of little practical value. Katrina is in the past. Far more important is learning something for the future, as this could help reduce the risk of further tragedies. Better protection against hurricanes will be an obvious discussion point over the coming months, to which as climatologists we are not particularly qualified to contribute. But climate science can help us understand how human actions influence climate. The current evidence strongly suggests that:
(a) hurricanes tend to become more destructive as ocean temperatures rise, and
(b) an unchecked rise in greenhouse gas concentrations will very likely increase ocean temperatures further, ultimately overwhelming any natural oscillations.

Scenarios for future global warming show tropical SST rising by a few degrees, not just tenths of a degree. That is the important message from science. What we need to discuss is not what caused Katrina, but the likelyhood that global warming will make hurricanes even worse in future.


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Tuesday, September 2, 2008

Phenomenon Floods and Drought


There are many pressures on water resources, including those arising from human activities. Additionally driving forces arise from the natural variability in water availability and climate change.Recent history has shown that extreme hydrological events as flood and droughts can create additional stress on water supplies essential for human and ecosystem health.

Climate change leads to increasing frequency of extreme weather events evident around the globe. Unusually high rain fall, which many scientists agree is due to climate change, is a significant cause of floods. On the other hand droughts are becoming longer, harder and more frequent.

Floods and droughts are the two important aspects of hydrological hazard. Floods usually result either from heavy precipitation (rain or snow) or from rapid snowmelt or glacier discharge (CliC). Droughts are caused by dry weather conditions in which evaporation exceeds the available surface water.

A flood is an overflow of water, an expanse of water submerging land, a deluge. Flooding and its impactsn are often influenced by a combination of natural factors and human interference. Floods are the most common natural desasters in Europe and, in term sof economic damage, the most costly ones. Major floods that used to happen only once in 100 years now take place every 10 or 20 years. Flooding can be disastrous. Houses can be destroyed, lives can be ruined, and wildlife threatened. Climate change is not the only cause of floods. Other ill-considered human activities play a key role as well. Upstream forests are able to soak up a lot of water, but if humans are destroying these areas, we increase the risk of floods.

A drought is an extended period where water availability falls below the statistical requirements for a region. Also drought is not a purely physical phenomenon, but an interplay between natural water availability and human demands for water supply. Since the demand for European water resources is increasing, also the pressure on water continues to grow and Europe is becoming increasingly vulnerable to the effects of periods without rainfall. Droughts are the prolonged absence of water in a specific area. Droughts kill a lot more people than floods because the effects are more prolonged. Droughts are always naturally caused, usually because changes in weather patterns greatly decrease the rainfall to an area. This is common in the southern edge of the Sahara desert, where there are usually extended periods of rainprovide the region with the water it needs for the year. However, it has become increasingly common for the rains to be very weak, or not come at all. A glaring example was a five year drought in the area from 1968-73. Today, the effects of global warming are seen as the Sahara expands due to these droughts.

Reducing the effects of flood and droughts (water disaster)
1. Disaster preparedness
The aim of disaster preparation is to be able to reduce the immediate mortality and morbidity with a better prepared, well equipped service. The preparation includes early warning systems for seasonal changes in climate, the ENSO, and risk of flood or drought, such as electronic information systems and satellites that can provide information over large regions and continents. Separate systems are needed to cater for the agricultural sector, cities and people in rural or remote communities. The public health infrastructure is particularly important for the immediate measures needed and for public information on reducing the health risks. Being prepared also means thorough disaster contingency plans, covering emergency housing, repairs, replacement of essential equipment and protection of the most vulnerable people in the community: the sick, the very young and the old. Improvement of water supply and sanitation systems is an important way of reducing the effects of a water disaster: countries with a good infrastructure for drainage and disposal of human waste and adequate water supply facilities have far fewer direct health problems during water-related disasters Sanitary inspections are an important tool to assess the water supply and sanitation facilities and these should be conducted systematically. The logistics of the predicted need for health and social services also need to be laid down in advance, including early warning systems to detect health effects. Planning should be on a regional, national and international level and include planning for climate change: as global warming and its water effects will increase the frequency of water disasters. Finally, public information and education can serve two purposes in preparing for disasters: ensuring early warnings to communities at risk; and giving information about how to conserve water and keep it safe from contamination.

2. Disaster mitigation
Once a disaster has occurred, or has been identified, all the measures in disaster preparedness will be needed and if not in place, outside help is probably needed. At the least, the mitigation efforts must include:
Emergency housing, especially after floods, but also if a drought has caused mass population movement in an attempt to find better water and food supplies.
Provision of emergency supplies of safe drinking water.
Emergency repairs to homes, drains and water supply and sanitation infrastructure.
Early warning systems to identify health effects and to detect rise in mosquito borne diseases, such as malaria, and diarrhoeal diseases, such as cholera. For such systems to be effective, a good public health information system is essential so that epidemiological trends can be monitored.

Both disaster preparedness and its mitigation require multisectoral cooperation and joint planning. Both need evaluation after a disaster to reduce the ill effects of later crises. While our world is never likely to be free of water disasters, there is much that can be done to minimise their health effects.

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Friday, August 29, 2008

Climate Change and World Food Production Security

There any significant change in climate on a global scale should impact local agriculture and thereby affect the world's food supply. Considerable study has gone into the questions of how farming might be affected in different regions, and by how much; and whether the net result may be harmful or beneficial. Overall, climate change, including global warming and increased climate variability, could result in a variety of impacts on agriculture. Some of these effects are biophysical, some are ecological, and some are economic.

Food security has been defined as "access by all people at all times to enough food for an active, healthy life" (World Bank, 1986). The World Food Summit, convened in 1996 and in 2002 by the Food and Agricultural Organization of the United Nations (FAO) in Rome, highlighted the basic right of all people to an adequate diet and need for concerted action among all countries to achieve this goal in a sustainable manner. How vulnerable households, regions and countries are to climate change's impacts on agriculture will depend on their access to land, water, and government support and action.

Since the late 1950s, global agricultural output has increased at rates and to levels that are unprecedented in human history. Much of the productivity increase is attributed to the breeding of high-yielding crop varieties, intensive use of inorganic fertilizers and pesticides, expansion of irrigation, and capital-intensive farm management.

In the 1970s, the euphoria surrounding the 'Green Revolution' was questioned in the wake of the energy crisis and growing awareness of long-term environmental consequences. Concern over soil erosion, groundwater contamination, soil compaction and decline of natural soil fertility, and destruction of traditional social systems, led to a reappraisal of what were then considered to be the most advanced agricultural production techniques. Since then, agricultural research has expanded its scope to include sustainable and resource-efficient cropping systems and farm management practices.

Since the beginning of the 1980s yet another threat to agriculture has attracted much attention. Many climatologists predict significant global warming in the coming decades due to increasing atmospheric carbon dioxide and other trace gases. As a consequence, major changes in hydrological regimes have also been forecast to occur. The magnitude and geographical distribution of such climate-induced changes may affect our ability to expand food production as required to feed a population of more than 10 000 million people projected for the middle of the next century. Climate change could have far-reaching effects on patterns of trade among nations, development, and food security.

Beyond what is known about greenhouse gases and the climate system, however, lie great uncertainties: How much warming will occur, at what rate, and according to what geographical and seasonal pattern? What secondary processes will the warming trend induce, and what might be the physical and biological impacts of such processes? Will some areas benefit while other areas suffer, and who might the winners and losers be? And, if such damages are unavoidable, what can be done to adapt or modify our systems so as to minimize or overcome them? These are important and complex questions, and we have only begun to understand them and to develop methods for their analysis.

Scenarios of climate change were developed in order to estimate their effects on crop yields and food trade. A climate change scenario is defined as a physically consistent set of changes in meteorological variables, based on generally accepted projections of CO2 (and other trace gases) levels. The range of scenarios analysed is intended to capture the range of possible effects and to set limits on the associated uncertainty.

The effects on crop yields in mid- and high-latitude regions appear to be positive or less adverse than those in low-latitude regions, provided the potentially beneficial direct physiological effects of CO2 on crop growth can be fully realized. From a development perspective, the most serious concern relates to the apparent difference in incremental yield impacts between developed and developing countries. The scenario results suggest that if climatic change were to retard economic development beyond the direct effects on agriculture in the poorer regions, especially in Africa, then overall impacts could be sizeable.

In all climate change scenarios, relative productivity of agriculture changes in favour of developed countries, with implications on resource allocation. Economic feedback mechanisms are likely to emphasize and accentuate the uneven distribution of climate change impacts across the world, resulting in net gains for developed countries.

The worst situation arises from a scenario of severe climate change, low economic growth, continuing large population increases, and little farm-level adaptation. In order to minimize possible adverse consequences, like production losses, food price increases, environmental stresses, and an increase in the number of people at risk of hunger, the way forward is to encourage the agricultural sector to continue to develop crop breeding and management programmes for heat and drought conditions, in combination with measures taken to preserve the environment, to use resources more efficiently, and to slow the growth of the human population of the world. The latter step would also be consistent with efforts to slow emissions of greenhouse gases, and thus the rate and eventual magnitude of global climate change.

Countries in the temperate zone may reap some benefits from climate change, many countries in the tropical and subtropical zones appear to be more vulnerable. Particular hazards are the possibly increased flooding of low-lying areas, the increased frequency and severity of droughts in semi-arid areas, and potential decreases in attainable crop yields. It happens that the latter countries tend to be the poorest and the least able to make the necessary economic adjustments. Much of the expected change in global climate is due to the past and present activities of the industrial countries; so it is their responsibility to commit themselves to, and to play an active role in, a comprehensive international effort to prepare for the likely consequences.

Climate change impact potentially significant for future agricultural production is soil organic matter loss due to soil warming. Considering the vulnerability of agricultural production to the occurrence of climate extremes, research should be directed to determine what are the heat-tolerance limits of currently grown and of alternative crops and varieties. At what threshold values of air or soil temperature do severe problems begin? What agronomic methods are the best to moderate the thermal regime affecting crop growth?

Modification of agronomic practices, adoption of crops known to be heat-resistant and drought-resistant, increased efficiency of irrigation and water conservation, and improved pest management. Such adjustments are worthy of being implemented in any case, be it with or without climatic change.


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Kilimanjaro Update The Indicator of Global Warming

The ice cap on Mount Kilimanjaro in Tanzania was formed almost eleven thousand years ago. Today, because of global warming, the ice cap is projected to disappear by 2020. Currently, eighty percent of the glacial ice on Kilimanjaro has melted, and in just 110 years (1910 - 2020) the ice cap will be gone. For glacial ice that took thousands of years to form to melt so quickly, one can only conclude that human activity during the last century has been a significant contributor to the change in the environment.

Kilimanjaro 1912

Kilimanjaro 2000

Our ability to influence a repair to the world environment may only be within the next few years. Without a significant global change in attitude and response to eliminate pollution, the world may soon enter an unrecoverable phase, bringing an uncontrollable demise to the Earth's ecology. If this occurs, no matter how hard we try, we will not be able to overcome the downward trend of the world's environment.

The scenario humanity must prevent is outlined in this paragraph. If global temperatures rise beyond previously recorded levels, the abnormally high heat will kill plant life. If a significant amount of vegetation dies due to high temperatures, the capacity for global conversion of CO2 to O2 on Earth will drop. Higher levels of CO2 will cause a further increase in Earth temperature and cause further plant destruction in a chain reaction. Global CO2 levels will then accelerate even higher, and vast areas will become deserts. Shortages of fresh water will occur and cause human populations to erode quickly. Even today, we may be close to entering this scenario. Scientists are already blaming the rise in ocean temperatures off the coast of Australia for the significant decline of the coral along the Great Barrier Reef.

Throughout the world, many species of plants and animals that took millions of years to evolve have already died because of pollution. There are 11000 species of plants and animals threatened at this very moment, and most from the destructive influences of air and water pollution created by humanity. Conservation of the planet and the building of environmental economic infrastructures to save it are essential. We have the intellect to survive, but are currently taking little decisive action to create sustainability for ourselves.

Working together within the United Nations, humanity could plan a solution for the Earth where all of us live with close to zero impact on the environment. The Earth will save us if we save it. Wars and religious differences must be overcome so that mankind can rapidly chart an economic path for survival. Humans are just one organic element on Earth, and the other animals, plants and micro-organisms are essential for our existence.

From an economic perspective, the restoration of the Earth will only occur when the word 'profit' is equated to environmental restoration and sustainability. The greatest challenge we have ever faced in our human existence is whether we have the capacity to collectively save the planet. We must act while we still have a chance!

The shrinking glacier is an iconic image of global climate change. Rising temperatures may reshape vegetation, but such changes are visually subtle on the landscape; by contrast, a vast glacier retreated to a fraction of its former grandeur presents stunning evidence of how climate shapes the face of the planet. Viewers of the film An Inconvenient Truth are startled by paired before-and-after photos of vanishing glaciers around the world. If those were not enough, the scars left behind by the retreat of these mountain-grinding giants testify to their impotence in the face of something as insubstantial as warmer air.

But the commonly heard—and generally correct—statement that glaciers are disappearing because of warming glosses over the physical processes responsible for their disappearance. Indeed, warming fails spectacularly to explain the behavior of the glaciers and plateau ice on Africa's Kilimanjaro massif, just 3 degrees south of the equator, and to a lesser extent other tropical glaciers. The disappearing ice cap of the "shining mountain," which gets a starring role in the movie, is not an appropriate poster child for global climate change.

The fact that glaciers exist in the tropics at all takes some explaining. Atmospheric temperatures drop about 6.5 degrees Celsius per kilometer of altitude, so the air atop a 5,000-meter mountain can be 32.5 degrees colder than the air at sea level; thus, even in the tropics, high-mountain temperatures are generally below freezing. The climber ascending such a mountain passes first through lush tropical vegetation that gradually gives way to low shrubs, then grasses and finally a zone that is nearly devoid of vegetation because water is not available in liquid form. Tropical mountaintop temperatures vary only a little from season to season, since the sun is high in the sky at midday throughout the year. With temperatures this low, snow accumulates in ice layers and glaciers on Kilimanjaro, Mount Kenya and the Rwenzori range in East Africa, on Irian Jaya in Indonesia and especially in the Andean cordillera in South America, where 99.7 percent of the ice in tropical glaciers is found.

A simple, physically accurate way to understand the processes creating and controlling these and other glaciers is to think in terms of their energy balance and mass balance.

Mass balance is merely the difference between accumulation (mass added) and ablation (mass subtracted); in this case mass refers to water in its solid, liquid or vapor form. A glacier's mass is closely related to its volume, which can be calculated by multiplying its area by its average depth. When a glacier's volume changes, a change in length is usually the most obvious and well-documented evidence. Alaska's vanishing Muir Glacier, an extreme case, shrank more than 2 kilometers in length over the past half-century.

Glaciers never quite achieve "balance" but rather wobble like a novice tightrope walker. Sometimes a change in climate throws the glacier substantially out of balance, and its mass can take decades to reach a new equilibrium.

Added mass comes largely from the atmosphere, generally as snowfall but also as rainfall that freezes; in rare cases mass is added by riming, in which wind carries water droplets that are so cold that they freeze on contact.

The most obvious subtractive process is the runoff of melted water from a glacier surface. Another process that reduces glacial mass is sublimation, that is, the conversion of ice directly to water vapor, which can take place at temperatures well below the melting point but which requires about eight times as much energy as melting. Sublimation occurs when the moisture in the air is less than the moisture delivered from the ice surface. It is the process responsible for "freezer burn," when improperly sealed food loses moisture.

Observations of Kilimanjaro's ice from about 1880 to 2003 allow us to quantify changes in area but not in mass or volume. The early European explorers Hans Meyer and Ludwig Purtscheller were the first to reach the summit in 1889. Based on their surveys and sketches, but mainly from moraines identified with aerial photographs, Henry Osmaston reconstructed (in 1989) an 1880 ice area of 20 square kilometers. In 1912, a precise 1:50,000 map based on terrestrial photogrammetry done by Edward Oehler and Fritz Klute placed the area at 12.1 square kilometers. By 2003 that area had declined to 2.5 square kilometers, a shrinkage of almost 90 percent. Much of that decline, though, had already taken place by 1953, when the area was 6.7 square kilometers (down 66 percent from 1880). Over the same period, ice movement has been almost nil on the plateau and slight on the slopes. There are indications that the slope glaciers at least are coming into equilibrium.

This pacing of change is at odds with the pace of temperature changes globally, which have been strongly upward since the 1970s after a period of stasis. Other glaciers share this pacing, with many coming into equilibrium or even advancing around the 1970s before beginning a sharp retreat.

Temperature trends are difficult to evaluate, owing to the paucity of relevant measurements, but taken together the data presented in the 2007 report from the IPCC (Intergovernmental Panel on Climate Change) suggest little trend in local temperature during the past few decades. In the East African highlands far below Kilimanjaro's peaks, temperature records suggest a warming of 0.5-0.8 degree during 1901-2005, a nontrivial amount of warming but probably larger than the warming at Kibo's peak. For the free troposphere, a deep layer including Kibo's peak, the warming rate during the period 1979-2004 for the zone 20 degrees latitude north and south of the equator was less than 0.1 degree per decade—smaller than the surface trend for that time and not statistically different from zero. Averages over a deep layer of the atmosphere, however, may be a poor estimate of the warming at Kilimanjaro's peak, although it has been argued that the warming must be nearly the same at all longitudes in the tropics, given that rotational effects are small, imposing strong dynamical constraints.

Focusing on measurements of air temperatures at the 500-millibar air-pressure level (roughly 5,500 meters altitude) from balloons, one paper suggests a warming trend in the tropical middle troposphere from about 1960 to 1979, followed by cooling from 1979 to 1997, although this study has not been updated.

Two of the data sets used to derive the tropical averages above are "reanalysis" data sets, in which observations are fed into a global dynamical model, thereby providing dynamically consistent fields of temperature, winds and so on, even where there are no observations. At the reanalysis point closest to Kilimanjaro's peak, there seems to be no trend since the late 1950s. But like the balloon and satel-lite data, the reanalysis data can be unsuitable for documenting trends over time .

When pieced together, these disparate lines of evidence do not suggest that any warming at Kilimanjaro's summit has been large enough to explain the disappearance of most of its ice, either during the whole 20th century or during the best-measured period, the last 25 years.

Glaciers and Global Climate
The observations described above point to a combination of factors other than warming air—chiefly a drying of the surrounding air that reduced accumulation and increased ablation—as responsible for the decline of the ice on Kilimanjaro since the first observations in the 1880s. The mass balance is dominated by sublimation, which requires much more energy per unit mass than melting; this energy is supplied by solar radiation.

These processes are fairly insensitive to temperature and hence to global warming. If air temperatures were eventually to rise above freezing, sensible-heat flux and atmospheric long-wave emission would take the lead from sublimation and solar radiation. Since the summit glaciers do not experience shading, all sharp-edged features would soon disappear. But the sharp-edged features have persisted for more than a century. By the time the 19th-century explorers reached Kilimanjaro's summit, vertical walls had already developed, setting in motion the loss processes that have continued to this day.

An additional clue about the pacing of ice loss comes from the water levels in nearby Lake Victoria. Long-term records and proxy evidence of lake levels indicate a substantial decline in regional precipitation at the end of the 19th century after some considerably wetter decades. Overall, the historical records available suggest that the large ice cap described by Victorian-era explorers was more likely the product of an unusually wet period than of cooler global temperatures.


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Tropical Storm Gustav Cause Oil Prices Rise


Oil prices swung higher Tuesday as Hurricane Gustav struck Haiti, raising concerns that the storm could slam into major oil operations in the Gulf of Mexico. However, the price rise was tempered by a stronger dollar and a report from the Energy Department showing even slower fuel demand than many traders thought.

After dropping as low as $112.36 per barrel in overnight trading, light, sweet crude for October delivery ended the day up $1.16 to settle at $116.27 a barrel on the New York Mercantile Exchange.

Gustav formed Monday and roared ashore Haiti Tuesday as a Category 1 hurricane. The storm triggered flooding and landslides that killed 23 people in the Caribbean. It weakened into a tropical storm, though it is likely to grow stronger in the coming days by drawing energy from warm open water. Gustav is the first storm of the 2008 Atlantic hurricane season to pose a serious threat to offshore oil and gas installations in the Gulf. In 2005, Katrina and Rita destroyed 109 oil platforms and five drilling rigs.

Tropical storm Gustav became a Category 1 hurricane early Tuesday as it approached Haiti's southern coast. The Miami-based National Hurricane Centre said Gustav could become a Category 2 storm with winds of 155 kilometres per hour or higher before hitting Haiti, and that Gustav will gather strength over the Gulf's warmer-than-usual waters.

Another weather forecaster, Accuweather.com, said that if Gustav passes through the Yucatan Channel into the Gulf, the storm could intensify into a Category 4 or 5 hurricane. A Category 5 hurricane is defined as having sustained winds over 250 kilometres per hour; hurricanes Rita and Katrina were Category 5 hurricanes, and shuttered most of the Gulf region's crude oil and natural gas production in the late summer and early fall of 2005.

With top sustained winds just below hurricane strength, Gustav was projected to become a major Category 3 hurricane after it passes between Cuba and Mexico and enters the warm, deep Gulf waters. Some models showed Gustav taking a path toward Louisiana and other Gulf states devastated by hurricanes Katrina and Rita three years ago. Vast areas of the Gulf lost power when Katrina struck, and utility companies say they're better prepared to respond to violent weather, but that only so much can be done.

Gustav is particularly worrisome because there are few surrounding wind currents capable of shearing off the top of the storm and diminishing its power, the hurricane center said. "Combined with the deep warm waters, rapid intensification could occur in a couple of days."

By Wednesday evening, a slightly weakened Gustav had top winds of 45 mph. It was centered some 65 miles south of Guantanamo Bay, Cuba, and traveling west at 7 mph.

A hurricane warning was in effect for parts of Cuba, including the U.S. military base at Guantanamo, where base spokesman Bruce Lloyd predicted "a really wet night."

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Thursday, August 28, 2008

Hurricane Record

A hurricane is a type of tropical cyclone, which is a generic term for a low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earth's surface. Tropical cyclones are classified as follows:


Tropical Depression
An organized system of clouds and thunderstorms with a defined surface circulation and maximum sustained winds of 38 mph (33 kt) or less. Sustained winds are a 1-minute average wind measured at about 33 ft (10 meters) above the surface. While 1 knot = 1 nautical mile per hour or 1.15 statute miles per hour and is abbreviated as "kt".

Tropical Storm
An organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds of 39-73 mph (34-63 kt).

Hurricane
An intense tropical weather system of strong thunderstorms with a well-defined surface circulation and maximum sustained winds of 74 mph (64 kt) or higher.

Hurricanes are categorized according to the strength of their winds using the Saffir-Simpson Hurricane Scale. A Category 1 storm has the lowest wind speeds, while a Category 5 hurricane has the strongest. These are relative terms, because lower category storms can sometimes inflict greater damage than higher category storms, depending on where they strike and the particular hazards they bring. In fact, tropical storms can also produce significant damage and loss of life, mainly due to flooding.

The Summary for Policymakers in the 2007 United Nations Intergovernmental Panel on Climate Change (IPCC) states “There is observational evidence for an increase in intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures. There are also suggestions of increased intense tropical cyclone activity in some other regions where concerns over data quality are greater. Multi-decadal variability and the quality of the tropical cyclone records prior to routine satellite observations in about 1970 complicate the detection of long-term trends in tropical cyclone activity.

The detection of trends in tropical cyclone activity is complicated by the lack of long-term records. Don’t look now, but an article has appeared in the prestigious journal Nature entitled “Intense hurricane activity over the past 5,000 years controlled by El Niño and the West African monsoon.” The title suggests that someone has a 5,000 year record of hurricane activity and that the activity is controlled by El Niño and weather in West Africa – there is no suggestion that hurricane activity is controlled by greenhouse gases, planetary temperature, or sea surface temperatures in the Atlantic.

Jeffrey Donnelly and Jonathan Woodruff of the Woods Hole Oceanographic Institution in Massachusetts begin their article noting that “At present there is significant debate about the cause of observed multi-decadal variability of hurricanes in the North Atlantic. To detect long-term patterns in tropical cyclone activity, reliable proxy reconstructions that extend back before the instrumental record are needed.” Finding proxy records of intense hurricane activity requires some imagination and some help from Mother Earth, and the pair found exactly what is needed on Puerto Rico’s island of Vieques.

Imagine a nice tropical beach backed by a vegetated barrier ridge about 10 feet tall. Behind the ridge is a back-barrier lagoon that over time becomes a playa that is only periodically under water. During large hurricane events, which are common in Puerto Rico, the ridge is breached and a large amount of material is deposited on the playa. Donnelly and Woodruff extracted cores from the playa, and they note that “Cores collected from the site contain several metres of organic-rich silt interbedded with coarse-grained event layers comprised of a mixture of siliciclastic sand and calcium carbonate shells and shell fragments. These layers are the result of marine flooding events overtopping or breaching the barrier and transporting these barrier and nearshore sediments into the lagoon.” Organic material can be dated, and just like magic, a long-term record of intense hurricane activity is produced.

The pair finds that “On the basis of our age model an interval of relatively frequent intense hurricane strikes at Vieques is evident between 5,400 and 3,600 calendar years before present (yr BP, where present is defined as 1950 AD by convention), with the exception of a short-lived quiescent interval between approximately 4,900 and 5,050 yr BP. Following this relatively active period is an interval of relatively few extreme coastal flooding events persisting from 3,600 until roughly 2,500 yr BP. Evidence of another relatively active interval of intense hurricane strikes is evident between 2,500 and approximately 1,000 yr BP. The interval from 1,000 to 250 yr BP was relatively quiescent with evidence of only one prominent event occurring around 500 yr BP. A relatively active regime has resumed since about 250 yr BP (1700 AD).”

With respect to the linkage between higher sea surface temperatures (SSTs) and hurricane activity, the pair notes that “Given the increase of intense hurricane landfalls during the later half of the Little Ice Age, tropical SSTs as warm as at present are apparently not a requisite condition for increased intense hurricane activity. In addition, the Caribbean experienced a relatively active interval of intense hurricanes for more than a millennium when local SSTs were on average cooler than modern.” They found that hurricane activity over the past 5,000 years has been modulated by the El Niño / La Niña cycle and the strength of the West African monsoon, not by the sea surface temperatures in the Atlantic and certainly not by global temperatures.

Atlantic Hurricane and Tropical Storm Records
Earliest tropical storm formed: Subtropical Storm One, January 18, 1978, through January 23, 1978, 45 mph. Excluding this subtropical storm, the Groundhog Day Tropical Storm of 1952 February 2, 1952-February 3, 1952 with 50 mph winds was the earliest formed in a calendar year.

Earliest Hurricane formed in a calendar year: March 6, 1908 Hurricane

Earliest Category 3+ hurricane : Hurricane Able, May 15, 1951 (In May/June 1825 there was a major hurricane also, but there is less information available about it due to the records of the time.)

Earliest hurricane in existence in a calendar year: Hurricane Alice, January 1-6, 80mpg 1955 (and December 31, 1954), formed the previous year. The earliest tropical storm was Tropical Storm Zeta in 2005-2006 (see below)

Latest tropical storm formed: Tropical Storm Zeta, 11am AST, December 30, 2005. Previous, Hurricane Alice 1am EST, December 30, 1954.

Latest hurricane formed: Hurricane Alice 1am EST, December 30, 1954. The only two cross-season storms on record are Hurricane Alice in 1954-1955 and Tropical Storm Zeta 2005-2006 (See below).

Latest hurricane in existence from previous year: Hurricane Alice, 1954-1955, January 6, 1955 (see Tropical Storm Zeta, January 6, 2006 for the latest Tropical Storm in existence)

Strongest (most intense) hurricane: Hurricane Wilma 2005, 882 millibars (mb) (the previous most intense hurricane was Hurricane Gilbert 1988 at 888 mb)

Strongest land-falling United States Hurricane: Labor Day Hurricane of 1935, 160mph 892 mbar

Longest lived hurricane :Hurricane San Ciriaco, August 1899 (28 days), Hurricane Ginger September 1971 (27.25 days), Hurricane Inga September 1969, 24.75 days, Hurricane Kyle September 2002, 22 days, Hurricane Carrie, September 1957 & Hurricane Inez September 1966 (20.75 days).

Longest Category 5 hurricane: Hurricane Allen, 1980, reached Category 5 status on 3 occasions (Ivan and Isabel did the same, but Allen lasted longer). Hurricane Dog 1950 2.50 days; Hurricane Isabel 2003, Hurricane David 1979, Hurricane Mitch 1998 all 1.75 days.

Most storms per season: 28 in 2005 season (revised upward by 1 April 2006) (previous: 21 named storms in 1933).

Fewest storms per season (since 1965): 1983 4 storms; 1965, 1977, 1982, 1986, 6 storms; 1972, 1987, 1992, 1994, 7 storms

What happens if they run out of names? The Greek alphabet is used: Alpha, Beta, Gamma, Delta, Epsilon, Zeta, eta, theta,iota, kappa, lambda, mu, nu xi, omikron, pi, rho, sigma,tau,upsilon,phi, chi, psi, omega.

When do they start with the following season's names? January 1 of the year, not June 1st when the Atlantic hurricane season begins or May 15th for the Pacific hurricane season. However storms that overlap from one calendar year into another are not renamed.

Strongest January hurricane: Hurricane Alice, January 1955, 80 mph winds (peak January 2, 1955) (The naming is a story in itself since it became a tropical storm Dec 30, 1954 but advisories weren't issued until January 1955, so it was given the name Alice, which made it the second Alice for 1954 - at that time names were re-used each year), December 30, 1954-January 6, 1955. Tropical Storm Zeta December 30, 2005-January 6, 2006. Subtropical
Storm One, January 18, 1978 45 mph winds is the only storm formed in January.

Strongest February tropical storm: Groundhog Day Storm of 1952 February 2, 1952-February 3, 1952, 50 mph

Strongest March hurricane: March 6, 1908 Hurricane, category 2 storm.

Strongest April tropical storm: Ana 2003 (the only April storm in fact), April 20-April 24, 60 mph winds, 994 mb

Strongest May hurricane:Hurricane Able 1951 (Category 3), 1908 Hurricane (Category ?), Alma 1970 (Cat 1), Tropical Storm 1933, May 15, 1887 (70mph) & May 17, 1887 (60 mph), earliest two storms active at once. Tropical Storm One, May 22, 1948 (50mph). Tropical Storm One, May 19, 1940.

Strongest June hurricane: Hurricane Audrey, June 25-29, 1957 (145mph, 946 mbar) (see also Alma 1966, 130 mph, 970 mbar and Agnes June 14-25, 1972 did a lot of damage, 85mph, 977 mbar)

Strongest July hurricane: Emily, 2005 (161 mph top sustained winds - earliest recorded category 5 hurricane) (previous record: Dennis (150 mph) 2005; Hurricane #1 (140 mph) in 1926.

Strongest August hurricane: Allen 1980 899 mbar, 190 mph (see also Katrina, 2005 175 mph sustained winds, 902 mbar; Hurricane Camille, August 1969, 190 mph, 905 mbar; Andrew, August 1992, 175mph, 922 mbar)

Strongest September hurricane: Gilbert, 185 mph, 888 mbar, (see Rita, 2005 175 mph, 897 mbar; Hurricane Janet, 1955, 175mph 914 mb)

Strongest October hurricane: Wilma 2005, 175 mph, 882 mbar. Wilma became the most intense hurricane in the Atlantic Basin ever recorded.

Strongest November hurricane: Lenny, 1999, November 13-23. 155 mph, 933 mbar. Also notable for its eastward motion. Tied with Michelle in 2001 based on central pressure of 933 mbar, 140 mph wind.

Strongest December hurricane: 1925 Hurricane, December 4, 1925, (100mph); see Hurricane Epsilon 2005 , 85mph, 979 mbar and Hurricane Nicole of 1998 85mph; see also Hurricane Lili 1984 80mph. Hurricane Epsilon 2005 is the longest lasting December storm.
Season with most hurricanes: 2005 with 15 Hurricanes (previous record: 12 in 1969)

Most major hurricanes hitting the U.S.: 4 in 2005 (previous record: three in 2004). Major hurricanes are category 3+.

Most tornadoes spawned: Hurricane Frances, 2004 (123), Hurricane Ivan 2004 (117), Hurricane Beulah 1967, (115), Hurricane Katrina 2005 (30). Hurricane Andrew also was notable for its tornados in the South Miami area.

Most Category 5 Hurricanes in one season: 4 in 2005 (Emily, Katrina, Rita, Wilma) (previous record: two in 1960 and 1961)

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