Lecture 3 - Climate

Question 1

Dew/Fog harvesting

Answer 1

• water condensates on surfaces colder than the air
• even in very dry regions, there is dew
• most of it will evaporate within the first hot hours of the day, we need to get it deep enough into the soil so it doesn’t evaporate anymore
• best dew collector better than every mechanical, are plants
• the more layers the more cycles of water cyclyes used

https: //www.youtube.com/watch?v=ajbodAFqNbA
https: //www.youtube.com/watch?v=OnGR-j93JEw

Question 2

Orographic effect

Answer 2

• wind pushing humid air to the side of a mountain
• due to higher pressure up the mountain the clouds will lose their water before they rach the other side
• hence you have a rainy and a dry side

Question 3

Precipitation

Answer 3

• research the precipitation in your area
• is it evenly spread or cyclical? rain/dry season?
• find out about extreme rainfalls/storms through internet, neighbours, library or other records
• plan your swale sizes according to these extreme events
• stability of swale can decide about life/death of plants and animals
• always harvest and store rainwater, even in humid areas, drought can be man-made or an effect of climate change
• calculate monthly/yearly water fall and the run-off for your property

Question 4

Climate Analogs

Answer 4

• climate similair to yours on other parts of the world
• due to climate change, some species will die or move up
• look into climate analogs around the globe to identify plants that could fill up that space and function
• never introduce new species without thinking about the possible consequences

Question 5

Heat

Answer 5

• the darker the color the more radiation is absorbed
• albedo effect: the higher reflection (white surface) the lower the heating of that object
• water, rocks and even soil can function as a thermal mass
• low-grade heat: convection (heat that travels through gas/liquid)
• mid-grade heat: conduction (heat that travels through contact, solid-solid or liquid-liquid)
• high grade heat: radiation (heats up solids without heating up the air)
• factors that decide about heat of a climate are: latitude,t season, slope angle (sun or shade side) and air clarity

Question 6

Air Flow

Answer 6

• hot air goes up, cool air goes down
• can be used with openings in different hights to create a constant air flow

Question 7

Wind

Answer 7

• observe the patterns of wind on site through the direction of tree flags
• where do the strongest winds come from? what seasons?
• hot/cold winds?
• do they carry humidity, salt, toxic or organic material, etc.?
• can be a detrimental factor to inhibit plant growth

Question 8

Wind break

Answer 8

• increases growth and yields
• straight perpendicular edges, not parabolic (like Mollison had in his book)
• best 11.5 times wide as trees once they are mature
• accumulation of organic material due to slowing of wind above the windbreak
• have a permeable outer layer, that doesn’t block 100% of the wind so you don’t create unpredictable edge effects (bad example completely shut metal fence = acts like a wing)
• stream lines = smooth edges speeds up winds on edges (screw up on purpose the linear design)
• find native edge species around you, make a list and select for a beneficial polyculture, add from climate analogs if necessary
• may be necessary to protect the wind break as it establishes (temporary fence)
• only once wind break is established you can start planting the layers behind

Question 9

Landscape effects

Answer 9

• the further away from big masses of water the harsher the sommer/winters
• water mitigates these effects
• altitude: colder, big contrast between day/night, thinner air, less pressure, more radiation
• can’t replace temperate species in tropical climates just by going up, as there are more factors that differ than the temperature, like light cycles
• snow can act as a shield against frost at night, below it doesn’t get colder

Question 10

Climate change

Answer 10

• design for that 100 year storm/flood/draught
• climate change will make these events a lot more frequent
• design the most resilient system possible with species that are not adapted yet, but will in future warmings

Question 11

Soil building in tropics

Answer 11

• due to missing seasons and extreme plant growth the top soil is thinner and lot more vulnerable to till farming
• the fungi are vital for carbon sequestration
• more fungi that sequester in certain seasons in temperate climates
• don’t try the same soil building methods without adapting it to the different circumstances

Question 12

Carbon Sequestration

Answer 12

• we could place back all the CO2 into the soil within 50 years if we regenerate the soil
• fungi and microbes in healthy soil sequester CO2
• to reverse global warming we have to put back 2.1cm back into the soil
• just regenerating the prairie soils of the US would be enough to mitigate clmate change
• stop using NPK which cuts the sequestration in the soil
• there’s limit when mature forest phase is reached, only until then “carbon minus”

Question 13

Brittleness

Answer 13

• how does the land react to disturbance?
• either it will recover or turn to desert
• disturb your land and see what happens
• if it doesn’t recover it’s brittle
• check on local constructions sites, revisit after certain amount of times
• often arid is more likely to be brittle, but not always
• the time needed to recover can tell you about brittleness level

Question 14

Trees

Answer 14

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