P&E CS - Tropical monsoon and polar tundra Climates

CLIMATE AND CLIMATE CHANGE = characteristics and distributions of two climatic types and their influence on human activities and numbers.

How much of the world is affected by the tropical monsoon winds?

• over half the world’s population living in 21+ asian countries

• including some of most populated nations: china, india, japan etc

What are the characteristics of the tropical monsoon climate?

• distinguished by wet and dry seasons

• summer wet season is may-oct

• winter dry season nov-april

What is the tropical monsoon summer wet season?

• when overhead sun heats the land intensively creating area of low pressure where warm air above rises

• moist air from sea is sucked inland brining heavy rain especially when forced over high mountains or plateaus (eg himalayas) - relief precipitation

What is the tropical monsoon winter dry season?

• by nov overhead sun has moved southwards causing sea to get hotter than the land and wind directions are reversed

• therefor in winter cool dry winds blow from asian interiors to the sea, with moisture being lost over mountainous regions before reaching the coast.

Why do subsistence farmers depend so greatly on the tropical monsoon climate?

• rice is cultivated in the monsoon season

  • rich in carbohydrates, fiber and protein, so is a very important staple food.

• can be grown in wet flood plains (‘wet rice’ varieties) or in drier hillside areas that are irrigated (‘dry rice’ varieties) - widely used

• nothing is wasted as rice is threshed and winnowed (to separate straw from rice) with the ‘waste used to rear animals, for fires, or woven into baskets etc

• it just needs sufficient water for irrigation

How much of the world is affected/reliant on by the polar tundra climate?

in contrast to the monsoon climate, polar tundra climate supports fraction of number that monsoon does.

despite it’s low population it supports tundra and ice cap regions cover 20%+ of the earth

What are the characteristics of the polar tundra climate?

• at such high latitudes hours of sun can be long

• despite this it is very cold with average temperatures exceeding 0ºC for only a few weeks of the year

therefor human activities are restricted: fishing, adventure tourism, and mineral exploitation rather than lang based agriculture

Who relies on the polar tundra climate and why?

• tundra vegetation has supported indigenous people sustainably for thousands of years

• eg in northern canada and greenland inuit people have hunted caribou, seals and other animals in winter, and fished in summer sustainably

  • meets most of food and material needs - no waste

• this is due to low numbers over a vast area due to the constantly changing lifestyles they lead.

What are the impacts on agriculture with climate impacting the tropical monsoon season?

• traditional rice cultivation methods are. both water and labour intensive

• fears that climate change will make weather more unpredictable, particularly impacting levels of precipitation - may jeopardize rice production

• means research into less water intensive cultivation has been carried out for alternative methods

• however, a downfall of alternative methods is weeds pose more of a problem, meaning greater need for herbicides (expensive)

What is an example of a project to help reduce the threats that climate change poses to rice cultivation?

ClimaRice - norwegian project

assesses variations in climate and it’s impacts on water availability for rice production - has run trials in andhra pradesh and tamil nadu, India. trials demonstrates

• increased yields

• lower labour costs

• deeper root systems for efficient uptake of nutrients

• markedly reduced methane emissions generated from microbe activity in padi fields.

How may climate change impact the polar tundra climate?

for 30+ years northern high latitudes have been showing signs of climate change with warnings of up to 1ºC per decade.

climate modelling predictions project an continuation of these trends leading to …

• warmer wetter climate - widespread thawing of permafrost and glacial retreat

• shorter snow season

• reduced sea ice

• permafrost and slope instabilities

• changes in migration patterns of wildlife

How may climate change-induced differences in the polar tundra climate impact agriculture ?

• changes in wildlife migration patterns, such as caribou, will have large impacts on indigenous people, threatening sustainability of existing settlements and lifestyle

• however other opportunities of cultivation of vegetation may increase

• can create new access to fishing grounds with less ice however impacts habitats that rely on the ice for breeding and feeding.