What are positive and negative effects of increased CO2 and global warming?

Climates change in countries, the UK will soon have a French climate for growing grapes. This also means that the creatures that usually were only in the Mediterranean are now moving north (jellyfish etc.).

Winters and Summers will be more extreme, droughts, floods and suchlike.

Answer

CO2 levels in terms of total concentration in our atmosphere have increased (debateably) from 0.028% to 0.037% over the past 150 years. The earlier level is determined by using glacial samples from Vostok (270 ppm). When you look at the Vostok website they make mention of the fact that low carbon dioxide levels create working problems for the individuals working there. The current level of CO2 found in the atmosphere at Vostok is 278 ppm according to the latest reports.

Current measurements are done in a multitude of methods. There are 300 airports in the USA we sample, along with sensors on the front of aircraft. These two very dissimilar methods make this large change. If we take these two values with no question we see a jump in forcing from the sun of 3.5 watts per square meter of earths surface. This would be a negative effect. This heat is about the same as your MP3 player puts out spread out over a square meter of land or water going from surface to the ocean floor.

A positive effect of CO2 levels increasing would be this same increase in heat and CO2 levels acts as a fertilizer for plants. This increased growth though, would cause a drop in CO2 levels, bringing the system back into balance.

The 0.2 to 0.6 degrees of warmth we have seen since the mini ice age's low point has brought about little actual change on the planet.

The IPCC claims we could see as much as 3 mm of ocean level rise every decade if the temp were to go higher. We have seen none of the temperature rise now for over a decade. This would be very negative if you live 3 mm above sea level..... in ten years from now.

Experts disagree about 50-50 on storms increasing or decreasing due to temp change. We are currently at a 40 year low on hurricanes, so it is anyone guess on this matter. NASA robots and sattelites have shown cooling of our oceans over the past twenty years.