GLOBAL WARMING. 1. What is the greenhouse effect? 2. Are human activities leading to the warming of the global climate? 3. What will be the consequences of global for Jamaica? 4. What can you do to help?. Evidence of Global Warming?.
1. What is the greenhouse effect? 2. Are human activities leading to the warming of the global climate?3. What will be the consequences of global for Jamaica?4. What can you do to help?
Projected anthropogenic CO2 emissions from fossil fuel use, deforestation and cement production are shown for some of the IPCC emission scenarios. The highest emission scenario - IS92e - assumes moderate population growth, high economic growth, high fossil fuel availability, and a phase out of nuclear power; and the lowest emission scenario - IS92c - assumes low population growth, low economic growth, and severe constraints on fossil fuel supplies.
Temperature changesPast changes in Global Temperature
Over the last 400,000 years the earth's climate has been unstable, with very significant temperature changes going from a warm climate to an ice age in as rapidly as a few decades. The changes in climate have matched changes in CO2
Data from ice layers, corals & trees rings show 1000 years of temperature in the N. hemisphere. The 20th century's 1oF warming stands out.
Using the IS92 emission scenarios, projected global mean sea level increases relative to 1990 were calculated up to 2100. Taking into account the ranges in the estimate of climate sensitivity and ice melt parameters, and the full set of IS92 emission scenarios, the models project an increase in global mean sea level of between 13 and 94 cms between 2000-2100.
This is a good example of changes already observed in Alaska. Widespread loss of discontinuous permafrost will trigger erosion or subsidence of ice-rich landscapes, change hydrologic processes, and release CO2 and methane to the atmosphere.
1. Do nothing Now: global warming is not a major threat because climate has never been static throughout time so let’s do nothing.
2. Wait and see: let’s wait for more evidence of global warming before we take actions that will cost several millions
3. Take precautionary steps: let’s take small informed steps before there is overwhelming evidence for it may be too late to act if we wait.