Teaching Kids about Sunlight, Wind & Microclimatic Conditions

Throughout the year, the use of the space surrounding your home is directly impacted by the regional climate. It includes hot and cold temperatures, direct sunlight, shade, forceful winds and gentle breezes. The immediate area surrounding the home is called the microclimate. 

Although you do not have any control over the regional weather patterns, temperatures, annual precipitation rates, and what is known as the macroclimate, you can have an influence on the microclimate. This article will help you educate your children about these microclimatic conditions and will provide some tips on selecting appropriate plant materials. 

Of course, the microclimate is greatly influenced by the macroclimate and regional weather patterns; But what are some of the microclimatic conditions that influence our direct environment? What changes can be made to the microclimate to take advantage of light and wind impacts? How do you take advantage of cool summer breezes, and maximize the impact of direct sunlight in the winter season. Perhaps harsh winter winds can be blocked or shady areas created for summer heat reduction within the microclimate? 

Our microclimate is influenced by a variety of factors including:  solar radiation, surrounding air temperatures, air movement, sun orientation, humidity, topographical location, proximity to lakes, or waterfront exposure, urban environments and rural environments. 

For instance, a home located in an urban setting will typically have a higher temperature than a home on a sub-urban wooded lot. The urban setting will provide a vast amount of paved surface and a greater amount of sunlight penetration to these surfaces. The urban setting is like a “heat sink” where the roofs, buildings and paved surfaces heat-up and re-radiate the penetrated sunlight causing an increase in temperature, as opposed to a wooded lot in the suburbs that has a variety of trees which absorb and filter against direct sunlight exposure.

Another example is the location of your home.  A house set within a depression or valley will have less wind impact as opposed to a home located at a prominent elevation or along a ridgeline that will experience greater wind forces.

Understanding how to appropriately develop our landscapes to mitigate the impacts of light and wind can help us create a microclimate that can BENEFIT your wallet.  These green design initiatives can reduce summer cooling costs and lower winter heating bills.

WIND Impacts in your Garden:

• Your local weather bureau can provide the information on the direction of summer breezes and prevailing winter winds. For the majority of the United States, the direction of the summer breezes travel directly from the south / southwest. During the winter season the direction of the winds travel from the northwest. 

• (click image above for enlarged view)In climates with cold winters, the goal may be to block against these winter winds with a row of trees and shrubs while continuing to capture the winter sun and maximize solar exposure. A dense row of evergreens placed north and northwest works effectively against cold winter winds. 

• In warmer climates, the goal may be to block the summer sun while channeling a summer breeze. Placing a semi-circular row of deciduous trees and shrubs from southeast to southwest, with a break in the middle (south) can work affectively to channel a summer breeze. 

• And in temperate climates, perhaps the majority of the United States, you would want to employ both strategies to block against winter winds and also channel in summer breezes.

• On a smaller scale, if you intend to start some garden seeds, you may wish to put up a wind screen to help protect tender new transplants and seedlings from the drying effects of the wind.

SUNLIGHT Impacts in your Garden:

• Sunlight is essential for the development of your garden and landscape plantings. Proper placement and selection of plant materials can lower your heating and cooling costs significantly. With this in mind, a properly placed tree and developed landscape can reduce the need for air conditioning systems which can reduce carbon dioxide emissions.

• Like everywhere else in the world, the sun rises in the east and sets in the west. And in the United States, the sun travels east to west along a southern exposure. The solar angle changes from summer to winter but the sun continues to always travel east to west along the southern latitude. Understanding the direction of the sun and its impact to your landscape is important in the development of your garden and how you can take measures to develop a microclimate in your own landscape. 

• There are several ways that trees and shrubs can help cool the air: 1) Providing shade from the sun, 2) Reducing air temperatures through transpiration, and 3) Reducing wind speeds and by absorbing heat.

• Temperatures within the vicinity of trees that barricade us from the direct impact of the sun will create a cooler environment for our landscape. The cooling is also accomplished through evaporation of water through the leaves. Of course, the larger the tree the greater the cooling.

• (click image above for enlarged view)Adding trees within urban settings is essential to help reduce the “heat island effect” in cities. Cities naturally (or should I say un-naturally) have a higher temperature than that of their surrounding suburban localities.  This is due to the fact that much of an urban environment includes so many impervious surfaces, such as roofs, concrete and asphalt paved surfaces. Placing trees, shrubs, and developing as much green space, such as adding a rooftop garden within urban environments helps greatly mitigate against this “heat island effect” and moderately reduce temperatures caused by direct sunlight impact. 

• (click image above for enlarged view)In cold or temperate climates the goal may be to capture as much sun as possible during the winter season.  Deciduous trees (meaning trees that drop their leaves in the winter season) can be placed along the path of sunlight impact to accomplish both strategies. Appropriate placement of these trees will help maximize a cooling effect in the summer while providing needed solar exposure for as much heat gain in the winter season.

Although we can’t change our regional weather or macroclimatic conditions, we can teach our children how to effectively analyze our own garden and landscape at a microclimatic level and make adjustments. 

A “green approach” will allow you to save money and (literally) create your own “cool place” in the garden with your kids. Teaching them how they can influence their microclimate is a fantastic green initiative you can do together!