global warming 1 Flashcards
why does the IPCC receive criticism?
2010 - mistakes and wrong data over melting of Himalayan glacier
2019 - under estimating pace and impact of climate change
why is global warming such a debate?
Its a global issue - not just gonna go away
political dimension eg conservative vs labour
Donald trump sceptic - economic impact on western world if we mitigate
science and earth systems ate complicated - models aren’t fully correct/ error bars
is flooding in the UK related to climate change?
maybe
also due to river regulations and increase in builidng on flood plain
are heatwaves and warmest years related to climate change?
most likely if theres evidence
10 warmest years have been recent eg 2016/9/15
are hurricanes related to climate change?
likely
as it creates warm oceans, low pressure systems , rise in sea level
define weather
mix of events that happen each day in the atmosphere including temp - humidity - rain
define climate
average weather pattern in a place over many years
what 4 things control earths climate?
green house gases
solar radiation
polar ice
ocean circ pattersn
what is the United Nations Framework Convention on Climate Change UNFCCC?I
International treaty priduced by united nations conference in 1992 (earth summit)
objective - stabilise greenhouse gas concentrations in atmosphere at a level which prevents dangerous climate change
this is framework
what is the Kyoto protocol?
sets binding targets for 37 industrial used countries and European community for reducing GHG emissions
legally binding in feb 2005
but not all nations ratified protocol
What is the Paris Agreenment ?
mitigation - reduce emissions
keep temp well below 2 degrees above pre-industrial levels
aim to limit incrase to 1.5 degrees
supports developing countries
monitor and evaulate progress
what is the intergovernmental panel on climate chanfe IPCC
Scientific body which assesses current state of climate change and its environment and socio-ecnomic consequneces
doesn’t carry out own research and work - publicate assessment reports and review clmate change science
how much nitrogen in atmopshere
78%
How much oxygen in atmos
20%
how much co2 in atmos
0.04%
how much methane in atmos
0.00018%
describe the snow ball earth theory
650 million years ago in pre-Cambrian period whole earth covered in ice from poles to tropics
life only survived in ice free forms or when sun penetrated the snow and melted it to allow photosynethesis
describe the process of solar radiation entering atmosphere
incoming short wave radiation reaches earths surface and heats it up
some heat reflected back to space called longwave radiation - infrared
some heat re-radiated and absorbed
most heat absorbed by GHG and reflected in all directions which warms earth in troposphere this makes earth habitable
name 5 main GHG
methane
carbon dioxide
nitrous oxide
water vapou
F gases - perfluro carbons and sulphur hexafluoride
define the ozone hole
region of very depleted ozone in stratosphere over Antarctic that happens at beginning of southern hesmisphere spring
what are man made chloroflouro carbons CFC
contribute to thinning of ozone layer
allow large quantities of harmful UV rays to reach earth
used in refrigerators - not using CFCs helps close ozone hole
how do we know atmospheric build up of GHG is due to humans ?
changes in the atmosphere of 14C and 12C ratio - as co2 release through fossil fuels is low in 14C so 14C has reduced in atmosphere
increase in co2 far exceeds boundary of natural variability
what were the pre industrial concentrations of carbon dioxide, methane and nitrous oxide
co2 - 280 ppm
ch4 - 700ppb
n20 - 275ppm
what are methane hydrate deposits
found in high arctic and continental shelves
stable under pressure deep in cold waters
when they warm up and pressure released when they become unstable
air burns them
global warming could lead to runaway warming effects - release of trapped methane in unstable deposits
what happened in eocene- super GHG
56- 33.9 mill years ago
abrupt warming of oceans due to release if gashydrates
