Why set the target at 2C ?

Event 1: the world is headed for a global warming of well over 3°C
A sobering new assessment by the "Climate Action Tracker" of the emission commitments and pledges put forward by industrialized and developing countries for the Copenhagen climate negotiations shows that the world is headed for a global warming of well over 3°C by 2100.

Carbon dioxide concentrations are projected to be over 650 ppm, with total GHG concentrations close to 800 ppm CO2 equivalent. From these numbers, there is at least a one in four chance of exceeding a warming of 4°C. This "Climate Action Tracker" is an independent science-based assessment, which tracks the emission commitments and actions of countries. The website provides an up-to-date assessment of individual national pledges to reduce their greenhouse gas emissions.

Event 2: Why is 3C warmer so much worse than 2C ?

"As honest curiosity: If we have seen a temperature increase of 0.57deg C over the past 100 years, when the CO2 levels went from 288 ppm to 365 ppm, how are current climate models managing to bring in temperature increases of up to (?) 6 degrees?"

After a temperature increase of 2 degrees above preindustrial levels the Earth reaches one of its natural 'tipping points'.

This basically means that various eco/climate systems operating within our planet begin to 'change gear', should this happen then we have 'run-away' climate change over which we have no control.

For example:

i) The tundra stretching across Russia,Siberia,Canada & the Arctic is ancient swamp land; previously frozen for millenia these swamps begin to release huge amounts of CO2 & methane as they deforst, (try Googling 'drunken trees' - its happening already).

ii) As the oceans heat up they begin to emit CO2 rather than retain it.

iii) Coral reefs bleach in hotter water, as they die they release CO2; once the reefs are dead the ocean ecosystems begin to collapse, with millions of tons of rotting vegetable matter, (dead fish) releasing yet more CO2.

iv) With less sea ice the dark waters of the ocean attract more sunlight increasing the temperature further.

It is the prevention of these and other 'positive feedbacks' which have the scientists so worried. Essentially once positive feedback loops begin, we completely lose control and it could take tens of thousands of years for the Earth's climate to return to its current state, if ever.

(Thanks to Clint Boon for his insights).

Progress:

They have encapsulated the outside-part of our heatpump today (see the attached picture). This "doghouse" has three purposes:

• Protect the heatpump


• Capture and maximize the effect of the exhaust air from the ventilation system (5-10C warmer than the surrounding air)


• Reduce the negative visual effect of a heatpump mounted on to the northfacing wall

Yes, we are still waiting for the team to reduce the noice level (inside and from the outside) - and hopefully they will change the point of entry for the heated air (from the heatpump). No progress to report today, but they have confirmed that the hand-over will take place on Tuesday next week.

The pictures below, shows the condense on the piping containing around 0C exhaust air.