Seen question

Question 1

what is a hurricane

Answer 1

a rapidly rotating storm system characterised by

• low pressure centre
• closed low level atmospheric circulation
• strong winds
• spiral arrangement of thunderstorms that produce heavy rain

Question 2

Hurricane conditions

Answer 2

• large areas of warm water (26oC)
• high pressure air masses flowing towards low pressure air zones
• unstable atmosphere
• instability generation in easterly trade winds

Question 3

Latitude generation

Answer 3

• tropical cyclones: 5-20o (any further north water is too cold)
• extra tropical cyclone: 20-70o (associated with frontal systems)

Question 4

Hurricane formation

Answer 4

• 10% of tropical disturbances develop into organised rotating storms
• disturbances = depression if winds increase and warm moist air drain in
• wind is deflected to the right via Coriolis effect

Question 5

Hurricane occurrences

Answer 5

• hurricanes obtain their energy from latent heat release in cloud formation process
• they occur where deep layers of warm water exist and during times of highest sea surface temp
• N.Hemisphere: august and september
• S.Hemisphere: January to march

Question 6

first record of Atlantic storms

Answer 6

• Hurricane Able, 1950
• paleo records look at events further into the past
  these events can be place and found in the Extended Hurricane Activity (EHA) index

Question 7

Burns and palmer, 2015

Answer 7

• caribbean deposits, jamaican sediments
• last 1000 years
• correlation between precip and tropical cyclone activity
• correlation between local rainfall and sediment chemistry
• lake level changes track precip shift in SST changes
• link between solar forcing and lake level change/EHA
• indicates enhanced heating increases frequency

Question 8

Toomey et al. 2017

Answer 8

• sediments in florida, Younger Dryas
• expectation = reduction in activity (cooler oceans)
• presence of turbidite layers in off-shore cores
• destabilisation during stormy conditions
• shutdown of northward Atlantic currents (intensity hurricanes)
• storm season SST warmer around Florida
• more frequent, high intensity during YD

Question 9

Coumou & Rahmstork, 2012

Answer 9

increase in frequency and magnitude of hurricanes

• warmer oceans
• moist atmosphere
• energy to sustain

Question 10

Intergovernmental Panel on Climate Change

Answer 10

• publish climate assessment since 1990
• predict global temp change by 1.4-5.8oC
• human influences have been detected in warming the atmosphere in 20th century and again now

Question 11

El Nino

Answer 11

• weaker pressure in pacific
• weaker trade winds
• warm pool migrating eastward
• downwelling
• lower biological productivity
• deeper thermocline in eastern pacific
• increase frequency of tropical storms in Pacific Ocean

Question 12

Hurricane Ophelia

Answer 12

• October 2017
• extratropical cyclone, category 3
• unusual conditions: warm moist gulf stream and an unusually cool atmosphere
• infrastructure damage
• 54 deaths

Question 13

Hurricane Debbie

Answer 13

• first tropical cyclone to hit UK and Ireland, 1962
• Tropical disturbance over Africa
• high sea surface temps (27oC) and a very low pressure system over W.Ireland
• category 3, downgrade to 1
  peak wind, 114mph
• downed powerlines, destroyed building, losses in agriculture, 18 fatalities
• $40-50 million in damage