2nd 5

Question 1

Target CO2 Emission

Answer 1

2 degrees Celsius is too high based on most recent research. There USA strong likelihood that the sea level response will be exponential and 29cm is not realistic

Models used to predict the 2 degree Celsius did not consider ice sheet decay = linear trajectory - exponential increase

Question 2

Dust group

Answer 2

Absorbs and scatters incoming shortwave radiation. Fertilises the oceans. Glacial periods contain higher dust content. Derived from South America exposed continental shelves and due to increased aridity. Most of the dust reaching Antarctica is from South America

Question 3

Temperature group

Answer 3

Hydrogen stable isotopes record temperature. Comparison from benthic O^18 from forums. Confirms temperature signal after 800Kyr

Question 4

CO2 group

Answer 4

Glacials= oceans are colder holding more CO2. Less upwelling due to increased sea ice and dust fertilisation causes increase phytoplankton and CO2 drawdown

Question 5

Pulling records together

Answer 5

Temperature and CO2 is the same

Dust leads up to 5,000 years in all of the records. Decrease I. Dust = change in winds or increase in sea level to reduce arid conditions.

One hypothesis for the rise in CO2 at the end of the last glacial maximum (termination) is that reduced iron (dust) supply to the southern ocean caused by the increase of 80-100ppm CO2