Global Climate Change and Ocean Current YSCN0029 Climate Change through Earth History Presented by: Jacky Poon, Candy Cheung, Connie Yu, Vannessa Poon, .

Is the Planet Warming? 10 warmest year records since 1990: 1998, 2002 & 2003 (joint), 2001, 1997, 1995,1990 &1999 (joint), 1991 & 2000 (joint). Analyses of over 400 proxy climate series (from trees, corals, ice cores and historical records) showed that 20 th century was the warmest century. The Inter-governmental Panel on Climate Change (IPCC) in its most recent report stated: “ most of the observed warming over the last 20 years is likely to have been due to the increase in greenhouse gas concentrations.” The warming leads to changes in ocean current and in the world.

10 warmest year records since 1990: 1998, 2002 & 2003 (joint), 2001, 1997, 1995,1990 &1999 (joint), 1991 & 2000 (joint).

Analyses of over 400 proxy climate series (from trees, corals, ice cores and historical records) showed that 20 th century was the warmest century.

The Inter-governmental Panel on Climate Change (IPCC) in its most recent report stated:

“ most of the observed warming over the last 20 years is likely to have been due to the increase in greenhouse gas concentrations.”

The warming leads to changes in ocean current and in the world.

Uneven distribution of sun’s energy Current movements

Uneven distribution of sun’s energy

Deep water wave Coriolis Effect

Deep water wave

Relationship between Atlantic Thermohaline Circulation and Global Warming Significant slowing of the ocean circulation that transfers warm water to the North Atlantic Ocean T he southern hemisphere would become warmer and the northern hemisphere would become colder Why? Result of Global Warming:

Significant slowing of the ocean circulation that transfers warm water to the North Atlantic Ocean

T he southern hemisphere would become warmer and the northern hemisphere would become colder

Higher temperatures under global warming I ncreasing the precipitation , melting nearby sea ice , mountain glaciers and the Greenland ice sheet A dd fresh water to the northern oceans The influx of fresh water reduce the surface salinity and density D ense water then sinks and slowly travels through the deep water southward into the Southern Hemisphere L ead to the significant slowing of the thermohaline circulation

Higher temperatures under global warming

I ncreasing the precipitation , melting nearby sea ice , mountain glaciers and the Greenland ice sheet

A dd fresh water to the northern oceans

The influx of fresh water reduce the surface

salinity and density

D ense water then sinks and slowly travels through the deep water southward into the Southern Hemisphere

L ead to the significant slowing of the thermohaline circulation

The North Atlantic Sink

Impacts of ocean current slow down D istinct regional variability Bitter winters as Little Ice Age 17 th -19 th centuries possibly related to changes in the strength of North Atlantic thermohaline circulation 10,000 years ago, a period called ‘Younger Dryas’ caused European temperature dropped >10C

D istinct regional variability

Bitter winters as Little Ice Age 17 th -19 th centuries

possibly related to changes in the strength of North Atlantic thermohaline circulation

10,000 years ago, a period called ‘Younger Dryas’ caused European temperature dropped >10C

The Day After Tomorrow? Solution The Framework Convention on Climate Change (UNFCCC) International Cooperation : Kyoto Protocol; USA rejected Produce less green house gases, eg CO2 , Methane China`s responsibility

Solution

The Framework Convention on Climate Change (UNFCCC)

International Cooperation : Kyoto Protocol; USA rejected

Produce less green house gases, eg CO2 , Methane

China`s responsibility