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.

Read More......

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.

Read More......

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.

Read More......

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.

Read More......