Global Warming impacts

In this section we will explore the many potentially serious to devastating potential impacts of global warming if it is allowed to continue for very much longer. Warming up the planet may not sound like a big deal, but there are many potentially dangerous, or expensive, or unhealthy impacts. The worst will not be immediate, but the decisions we make to day will establish level of impacts that occur in the future. We are making decisions our grandchildren cannot reverse, but to which they will need to adapt.

(Note: we are still building this section, so there is a lot more to come!)

Global warming is already happening

Global has already caused many major problems and these will only get worse. We have already seen:

• Heat waves have brought death to many people
• Increased costs for cooling and air conditioning
• Melting permafrost is releasing methane causing more global warming
• Melting mountain glaciers is already causing loss of freshwater supplies and if the mountain ice caps disappear, hundreds of millions of people will be affected
• Droughts are already causing farmlands to be abandoned in the Middle East and caused over 6 million people to be displaced form their homes as a result of the ensuing war. The US, Mexico, Asia, Africa and South America are all vulnerable.
• Increased flooding in major rivers due to temperature rising, which allows the air to hold more moisture which increases the amount of rain falling.
• Disease vectors and insect pests are breaching the distribution barriers
• Increased severity of storms and hurricanes
• Increased ocean acidification resulting in early loss of fisheries productivity. Species that have shells will increasingly have difficulty and already there is a severe loss of phytoplankton, the base of the productivity of the ocean.
• Sea level rise has already begun to have impacts:
  • inundate freshwater aquifers
  • flood coastal buildings and homes, livelihoods have been lost, and eventually entire cities will be threatened
  • drown islands, and the first of the climate refugees have already begun to move
  • cause millions of refugees to flee long-term drought in Europe

Sea Level Rise drowns coastal cities

What's the problem with a few feet of sea level rise? If you live by the sea or have a business near the beach - as do almost a billion people - it will be a major problem. A small rise of 2 m (6 feet) floods much of the Fort Lauderdale for example.

Extensive Drought Ruins food production

As the planet warms, certain areas will get much dryer and others much wetter. Major areas of drought will mean enormous losses of agricultural land so it will be increasingly difficult to feed a growing population of people.

Within the next 15 years we could see much of the southern and middle US, Mexico, northern South America, and much of southern Europe, the Middle East, southern Africa, and parts of Asia having to abandon farmland.

Locked-In Global Warming Impacts

A locked-in impact is one that is going to happen no matter what we do because we have made enough changes to the climate that we cannot reverse it in time to avoid the consequence of our actions. This is what today's temperature and CO2 levels will lock-in if we let it stay there for much longer.

Reduce Emissions to hold at 500 ppm CO2

• Minimum of 20m-40m sea level rise
• Destruction of coastal cities
• A billion refugees.
• Stronger hurricanes
• Heat waves become the norm
• Reduced agricultural production
• Loss of freshwater reserves for hundreds of millions of people in Europe, Asia, South America
• Mountain ice cap disappearance
• Loss of major rivers
• Lethal areas in the tropics for humans and other mammals
• Farming restricted to temperate and arctic regions
• Intensified desertification in sub-Saharan Africa, mid-USA, Mexico, parts of Africa, Asia, and Australia
• Pests and disease organisms invade from the tropical areas
• Sea water incursions into freshwater aquifers
• Loss of many organisms due to ocean acidification
• Ocean fisheries will decline as prey organisms decline
• Coral reef structures will decline causing coral island erosion

Future Effects of "Business As Usual"

• Sea level rise of 50m -80m over time, with as much as 1m in some decades
• Most Caribbean and many world atolls will be underwater
• Most of today's major coastal cities and infrastructure will be underwater
• Large methane releases from the Arctic and deep ocean
• Overloaded infrastructure and political systems
• Unstable civil society
• Intense storms and sea surges
• Disease vectors in temperate and Arctic regions with no protection
• Urban heat waves will be very dangerous
• Loss of mountain ice caps and sea water incursions will leave much of the world desperate for fresh water

Ten Degrees Celsius or More

An extinction threat to the human species. A warming of less than 7 degrees Celsius would cause some areas of the world to surpass the wet-bulb temperature limit, and a 11.5 degree Celsius warming would put half of the world's population in an uninhabitable environment. When it comes to evaluating the risk of carbon emissions, sometimes the stakes are too high, even if there is only a small chance of the worst case scenarios happening. In our case, continued CO2 emissions will guarantee at least a 12 degree Celsius rise within a few centuries.