Lecture 3 - Climate Flashcards
Why are plants adapted to adverse weather conditions?
Because they re unable to move away and so are adapted to conditions such as drought, flood, extreme heat etc.
How are animals adapted to adverse conditions?
Via their:
- endocrine system
- metabolism
- thermoregulation
What is the cause of latitudinal variation in solar radiation absorption?
Earth’s spherical shape is the cause of this.
Name factors which affect temperature?
- latitude
- proportion of land and ocean
- Earth’s rotation and tilt on axis
What creates seasons?
The tilt of the Earth’s axis and it’s orbit.
What is the definition of weather?
Short term atmospheric conditions at a particular time and space. Short term responses from animals to weather changes.
How does climate vary from weather?
Climate is an average of atmospheric conditions over a much longer period of time than weather. Longer responses by organisms to climate. Climate linked to radiation levels on earth.
Radiation
- Solar radiation drives climate patterns
- around 70% absorbed by atmosphere and earths surface in form of heat
- greenhouse gases trap heat
- solar radiation determines atmospheric air circulation and precipitation patterns
What Is the Albedo affect?
Darker surfaces (eg water and forests) absorb more radiation whereas lighter surfaces eg ice and snow reflect more radiation
Why is the Northern hemisphere slightly warmer than the southern hemisphere?
The northern hemisphere is around 2degrees C warmer tan the southern hemisphere as land radiates more heat than ocean and the northern hemisphere has a greater proportion of land.
How are atmospheric circulation cells created?
Surface air replaces rising air.
Coriolis effect
How objects veer towards different directions depending on what hemisphere they’re found in.
Where is Earth’s rotation at its fastest?
At the equator.
How is a gyre formed?
When a prevailing wind meets a continent
Why do the Northern and Southern hemispheres have different seasonal patterns?
Due to the tilt of the Earth’s axis.
What does ocean floor topography affect?
- water depth
- light penetration
- water temp., pressure, movement
Adaptations to temporal variation in climate:
- tolerance
- dormancy (eg. hedgehog hibernation)
- migration (bird migration in winter)
Adaptations to daily variation in climate:
- circadian rhythms - 24 hour cycle in physiological processes
- response to external cues such as sunlight and temp.
- birds sing in the morning
- slugs active at night
- mosquitoes bite at night
Spatial variation within climate has 3 scales:
- variation across climatic zones
- variation within a region
- microclimatic variation
Give an examples of organisms which are inhibited by temperature.
Case study 1: the plant wild madder’s growth is closely correlated with the 4.5 degree C January isotherm. Lower temps inhibit shoot development and growth.
Case study 2: The saguaro cactus is likely to die when kept below freezing for more than 36 hours.
Case study 3: Barnacle dies in summer temps above 25 degree C.
Give an example of an organism which has adapted to competition for radiation.
Case study 1: Vernal species - avoid competition for light by growing early in the season.
How do endotherms and exotherms differ in their adaptations to changes in temperature?
Endotherms
- regulate temp by producing heat within their body
- which requires a large amount of energy
- eg. birds, mammals
Ectotherms
- rely on external sources of heat
- killed by extreme temps
- perform slowly at lower than optimum temps
