global warming versus climate change

Climate Change — Changes in regional

climate characteristics, including temperature, humidity, rainfall, wind, and severe weather events.

Global Warming

Planet Earth's current warming trend is based largely on natural warming and cooling cycles that have been happening for eons; as well as human-caused additions to greenhouse gases, which are boosting the atmosphere's ability to trap heat in the biosphere. Minor factors like an overal

l increase in th

e sun's solar intensity play a smaller role.

While greenhouse gases are an essential component of a livable planet—they're what keep Earth from being a lifeless ball of ice—humans are causing greenhouse gas levels to increase so quickly that it's causing the aver

age global temperature to rise much faster than it would naturally.

This warming is predicted to lead to a variety of negative effects, including:

• Melting (and possible disappearance) of glaciers and mountain snow caps that feed the world's river s and supply a large portion of the fresh water used for drinking and irrigation.
• A rise in sea levels due to the melting of the land-based ice sheets in Greenland and Antarctica, with many islands and coastal areas ending up more exposed to storm damage or even underwater.
• Increasingly costly "bad weather" events such as heat waves, droughts, floods, and severe storms.
• Lowered agricultural productivity due to less favorable weather conditio ns, less available irrigation water, increased heat stress to plants, and an increase in pest activity due to w armer temperatures.
• Increases in vector-borne infectious diseases like malaria and Lyme Disease.
• Large numbers of extinctions of higher-level species due to their inability to adapt to rapidly changing climate and habitat conditions.

The first two of these effects are mostly related to increasing average temperatures. Items 3-6 are related to heat too, but also playing a role are non-temperature factors—i.e. "climate-change factors."

DIFFERENCES BETWEEN GLOBAL WARMING AND CLIMATE CHANGE

Climate Change—Beyond Withering Weather

Climate change is about much more than how warm or cool our temperatures are. Whereas "global warming" refers to increasing global temperatures, "climate change" refers to regional conditions. Climate is defined by a number of factors, including:

• Average regional temperature as well as day/night temperature patterns and seasonal temperature patterns.
• Humidity.
• Precipitation (average amounts and seasonal patterns).
• Average amount of sunshine and level of cloudiness.
• Air pressure and winds.
• Storm events (type, average number per year, and seasonal patterns).

To a great extent, this is what we think of as "weather." Indeed, weather patterns are predicted to change in response to global warming:

• some areas will become drier, some will become wetter;
• many areas will experience an increase in severe weather events like killer heat waves, hurricanes, flood-level rains, and hail storms.

It's tempting to think that all of these changes to the world's climate regions will average out over time and geography and things will be fine. In fact, colder climates like Canada may even see improved agricultural yields as their seasonal temperatures rise. But overall, humanity has made a huge investment in "things as they are now, where they are now." Gone are the days of millennia ago when an unfavorable change in climate might cause a village to pack up their relatively few belongings and move to a better area. We have massive societal and industrial infrastructure in place, and it cannot be easily moved. Climate-change effects will generally not be geographically escapable in the timeframe over which they happen, at least not for the majority of humans and species.

EFFECTS:

The effects of global warming and climate change are of concern both for the environment and human life. Evidence of observed climate change includes the instrumental temperature record, rising sea levels, and decreased snow cover in the Northern Hemisphere. According to the IPCC Fourth Assessment Report, "[most] of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in [human greenhouse gas] concentrations". It is predicted that future climate changes will include further global warming (i.e., an upward trend in global mean temperature), sea level rise, and a probable increase in the frequency of some extreme weather events. Ecosystems are seen as being particularly vulnerable to climate change. Human systems are seen as being variable in their capacity to adapt to future climate change.To reduce the risk of large changes in future climate, many countries have implemented policies designed to reduce their emissions of greenhouse gases.

Global Warming Effects

Green house gases stay can stay in the atmosphere for an amount of years ranging from decades to hundreds and thousands of years. No matter what we do, global warming is going to have some effect on Earth. Here are the 5 deadliest effects of global warming.

5. Spread of disease
As northern countries warm, disease carrying insects migrate north, bringing plague and disease with them. Indeed some scientists believe that in some countries thanks to global warming, malaria has not been fully eradicated.

4. Warmer waters and more hurricanes
As the temperature of oceans rises, so will the probability of more frequent and stronger hurricanes. We saw in this in 2004 and 2005.

3. Increased probability and intensity of droughts and heat waves
Although some areas of Earth will become wetter due to global warming, other areas will suffer serious droughts and heat waves. Africa will receive the worst of it, with more severe droughts also expected in Europe. Water is already a dangerously rare commodity in Africa, and according to the Intergovernmental Panel on Climate Change, global warming will exacerbate the conditions and could lead to conflicts and war.

2. Economic consequences
Most of the effects of anthropogenic global warming won’t be good. And these effects spell one thing for the countries of the world: economic consequences. Hurricanes cause do billions of dollars in damage, diseases cost money to treat and control and conflicts exacerbate all of these.

1. Polar ice caps melting
The ice caps melting is a four-pronged danger.

First, it will raise sea levels. There are 5,773,000 cubic miles of water in ice caps, glaciers, and permanent snow. According to the National Snow and Ice Data Center, if all glaciers melted today the seas would rise about 230 feet. Luckily, that’s not going to happen all in one go! But sea levels will rise.

Second, melting ice caps will throw the global ecosystem out of balance. The ice caps are fresh water, and when they melt they will desalinate the ocean, or in plain English – make it less salty. The desalinization of the gulf current will “screw up” ocean currents, which regulate temperatures. The stream shutdown or irregularity would cool the area around north-east America and Western Europe. Luckily, that will slow some of the other effects of global warming in that area!

Third, temperature rises and changing landscapes in the artic circle will endanger several species of animals. Only the most adaptable will survive.

Fourth, global warming could snowball with the ice caps gone. Ice caps are white, and reflect sunlight, much of which is relected back into space, further cooling Earth. If the ice caps melt, the only reflector is the ocean. Darker colors absorb sunlight, further warming the Earth.

CLIMATE CHANGE EFFECTS:

How much warming has happened? Scientists from around the world with the Intergovernmental Panel on Climate Change (IPCC) tell us that during the past 100 years, the world's surface air temperature increased an average of 0.6° Celsius (1.1°F). This may not sound like very much change, but even one degree can affect the Earth. Below are some effects of climate change that we see happening now.

• Sea level is rising. During the 20th century, sea level rose about 15 cm (6 inches) due to melting glacier ice and expansion of warmer seawater. Models predict that sea level may rise as much as 59 cm (23 inches) during the 21st Century, threatening coastal communities, wetlands, and coral reefs.
• Arctic sea ice is melting. The summer thickness of sea ice is about half of what it was in 1950. Melting ice may lead to changes in ocean circulation. Plus melting sea ice is speeding up warming in the Arctic.
• Glaciers and permafrost are melting. Over the past 100 years, mountain glaciers in all areas of the world have decreased in size and so has the amount of permafrost in the Arctic. Greenland's ice sheet is melting faster too.
• Sea-surface temperatures are warming. Warmer waters in the shallow oceans have contributed to the death of about a quarter of the world's coral reefs in the last few decades. Many of the coral animals died after weakened by bleaching, a process tied to warmed waters.
• Heavier rainfall cause flooding in many regions. Warmer temperatures have led to more intense rainfall events in some areas. This can cause flooding.
• Extreme drought is increasing. Higher temperatures cause a higher rate of evaporation and more drought in some areas of the world.
• Ecosystems are changing. As temperatures warm, species may either move to a cooler habitat or die. Species that are particularly vulnerable include endangered species, coral reefs, and polar animals. Warming has also caused changes in the timing of spring events and the length of the growing season.
• Hurricanes have changed in frequency and strength. There is evidence that the number of intense hurricanes has increased in the Atlantic since 1970. Scientists continue to study whether climate is the cause.
• More frequent heat waves. It is likely that heat waves have become more common in more areas of the world.
• Warmer temperatures affect human health. There have been more deaths due to heat waves and more allergy attacks as the pollen season grows longer. There have also been some changes in the ranges of animals that carry disease like mosquitoes.
  
• Seawater is becoming more acidic. Carbon dioxide dissolving into the oceans, is making seawater more acidic. There could be impacts on coral reefs and other marine life.

Causes of Climate Change

Figure 7y-1 illustrates the basic components that influence the state of the Earth's climatic system. Changes in the state of this system can occur externally (from extraterrestrial systems) or internally (from ocean, atmosphere and land systems) through any one of the described components. For example, an external change may involve a variation in the Sun's output which would externally vary the amount of solar radiation received by the Earth's atmosphere and surface. Internal variations in the Earth's climatic system may be caused by changes in the concentrations of atmospheric gases, mountain building, volcanic activity, and changes in surface or atmospheric albedo. Figure 7y-1: Factors that influence the Earth's climate. The work of climatologists has found evidence to suggest that only a limited number of factors are primarily responsible for most of the past episodes of climate change on the Earth. These factors include: Variations in the Earth's orbital characteristics. Atmospheric carbon dioxide variations. Volcanic eruptions Variations in solar output. What Causes Global Warming? Scientists have spent decades figuring out what is causing global warming. They've looked at the natural cycles and events that are known to influence climate. But the amount and pattern of warming that's been measured can't be explained by these factors alone. The only way to explain the pattern is to include the effect of greenhouse gases (GHGs) emitted by humans. To bring all this information together, the United Nations formed a group of scientists called the International Panel on Climate Change, or IPCC. The IPCC meets every few years to review the latest scientific findings and write a report summarizing all that is known about global warming. Each report represents a consensus, or agreement, among hundreds of leading scientists. One of the first things scientists learned is that there are several greenhouse gases responsible for warming, and humans emit them in a variety of ways. Most come from the combustion of fossil fuels in cars, factories and electricity production. The gas responsible for the most warming is carbon dioxide, also called CO2. Other contributors include methane released from landfills and agriculture (especially from the digestive systems of grazing animals), nitrous oxide from fertilizers, gases used for refrigeration and industrial processes, and the loss of forests that would otherwise store CO2. Different greenhouse gases have very different heat-trapping abilities. Some of them can even trap more heat than CO2. A molecule of methane produces more than 20 times the warming of a molecule of CO2. Nitrous oxide is 300 times more powerful than CO2. Other gases, such as chlorofluorocarbons (which have been banned in much of the world because they also degrade the ozone layer), have heat-trapping potential thousands of times greater than CO2. But because their concentrations are much lower than CO2, none of these gases adds as much warmth to the atmosphere as CO2 does. In order to understand the effects of all the gases together, scientists tend to talk about all greenhouse gases in terms of the equivalent amount of CO2. Since 1990, yearly emissions have gone up by about 6 billion metric tons of "carbon dioxide equivalent" worldwide, more than a 20% increase.