Water’s Influence on Weather & Climate

Weather vs. Climate ◦ Think/Pair/Share Weather – The condition of the atmosphere at a specific time during the day. Climate – A region’s generalized weather patterns, averaged over several decades. Water’s Influence on Weather & Climate

Large bodies of water have a moderating effect on the climate of the nearby region ◦ Timmins, ON - 17°C in Jul, -18°C in Jan ◦ Victoria, BC - 16°C in Jul, 5 °C in Jan  What do you notice about the temperature in Timmins vs. BC?  *note – they are along the same line of latitude The Moderating Effect

Water has a higher heat capacity than land or air – takes longer to absorb heat, and longer to release heat ◦ Heat capacity – Ability of a material to absorb heat The Moderating Effect

Effect: ◦ Day & Summer: Land gets hotter than water; warm air on land rises, cooler air from water blows in to replace it  Result: Cooler summers The Moderating Effect

Effect: ◦ Night & Winter: Water cools slower than land; warm air over water rises and cooled air over land moves in  Result: Milder winters The Moderating Effect

A helpful hint: ◦ At your cottage, which way does the fire blow during the day? At night?

A microclimate is an area with a localized climate variation that differs from the larger climate around it ◦ Ex. Point Pelee, ON – Sticks out into Lake Erie ◦ Ex. A greenhouse Microclimates

Farmers living close to the Great Lakes experience a much longer frost-free period than farmers in other parts of Ontario The warmer air from the lakes keeps nighttime temperatures on the shore above freezing longer into the fall Microclimates & Farming

Northern hemisphere - 39% land, 61% ocean Southern hemisphere - 19% land, 81% ocean Greater moderating effect on southern hemisphere’s climate Water & Global Climate

Coastal regions and other regions located near a large body of water tend to have more precipitation than regions further inland. ◦ Why?  As air travels across the water, it picks up a large amount of moisture (water vapour)  Results in more precipitation (rain & snow)  Coastal Storms – Hurricane Katrina Water and Precipitation

Water’s Influence on Weather & Climate Read and complete workbook pages In-class Assignment – Tuesday, October 25 th