Wednesday, July 27, 2011

Climographs

(http://www.cotf.edu/ete/modules/msese/earthsysflr/climograph.html)
How to Read a Climograph
Every place on Earth has weather. However, different places on Earth have different types of "typical" weather. Some places are dry, some are wet, some are hot, some are cold, and some are a little of everything!


You can find out what the weather is like where you live by looking out the window or by stepping outside. Weather refers to temperature, precipitation (rain and snow), and the wind's direction and speed. Scientists who study the weather collect information from different places on Earth and come up with averages, or typical types of weather, for a particular place. This average, or typical type of weather that occurs during a year, is called the "climate."
A quick way to get an idea of the climate of a particular place is to look at a "climate-graph," or "climograph." A climograph is what scientists create to show a particular location's average temperature and precipitation during the year.

Below is a climograph for Moose Factory, Canada. To help you learn to read a climograph, the different parts of the climograph have been identified by number. A description of each of the numbered parts is given below.

Image of a climograph for Moose Factory, Canada.  Please have someone assist you with this.1. The type of biome associated with the place.

2. The place where the temperature and precipitation were measured.

3. A scale used to indicate inches of precipitation.

4. The months of the year. The letters J, F, M, etc., stand for January, February, March, etc.

5. The temperature scale in degrees Fahrenheit. 6. A bar graph showing the average precipitation for each month. In this example, the average total precipitation is about 1 inch in January and nearly 4 inches in August. (Note: Values for this graph are found on the left-hand scale.)

7. A line graph showing monthly temperature during the year. In this example, the lowest temperature is about -5°F in January and the highest is about 45°F in July. (Note: Values for this graph are found on the right-hand scale.)
Cherie and Nicole :)

Weather and Climate: how it affects us

Weather is about daily (diurnal) changes in weather elements. Weather refers to the atmospheric conditions at a specific place (location) over a short period of time. Climate is about long term trends and generalisations of the weather over a long period of time (30-35 years). Climate refers to atmospheric conditions of a specific place (location).

(http://www.helium.com/items/1375628-impact-of-weather-on-population)

A look at how weather affects populations

Weather is the state of the air at a particular place and time - warm or cold, wet or dry, cloudy or windy or the likes. Climate is the normal pattern of weather experienced in a particular area over a long period.
The weather and climate of a place has always affected populations. Throughout history, humanity has always been in awe of the weather, and weather still plays a big part in our lives today. It affects many of the things that we do, from the clothes we wear and the food we eat, to where we live and how we travel.

INFLUENCE ON HUMAN MIGRATIONS AND GROWTH OF CIVILIZATIONS
Since the dawn of history human settlements, migrations and growth has depended on weather conditions. All the great civilizations and empires have flourished near rivers and oceans, where the weather is moderate and suitable for the cultivation of crops and domestication of animals.
Just to cite some instances from history, it is the pleasant climate of England that attracted the various invaders of the past like Normans, Danes and others to settle down, and gradually over the years assimilate to form what is now the English population. The harsh climate of the Arabian deserts have prevented the interiors of the land from being invaded by an external force in the annals of history, and moreover was an added incentive for the Arabs to burst out from that hot and barren land to establish one of the largest empires during the medieval period. The Arabs landed in Spain initially on an expedition, and attracted by the weather, stayed and ruled there for 800 years! Many once thriving cities are now abandoned ghost towns primarily because the weather changed and people could no longer continue with their lives there. A big tsunami in the Indian Ocean in 1341 CE wrecked havoc of most of the well-established ports and led to the formation of new natural harbors in places like Cochin and Karachi, which soon developed into big cities.

INFLUENCE ON THE WAY OF LIFE
Weather has an impact on the physical and mental make up of the populace as well. The culture, the way of life, the dietary habits, the clothing trends, the behavior of people coming from places where the weather in harsh differs significantly from that of people who live under docile climates. It is possible to stereotype the populace of cities and even nations based on weather related factors.

EFFECT ON MENTAL HEALTH AND MOODS
Weather also has a profound effect on human health and well-being. The hypothalamus in the human brain controls.

Weather Affects All Our Lives In Some Way


A very common proverb that is somewhat true is, no one does anything about the weather though everyone discusses about it. In fact it is one of the most common topic that people speculate and talk about. Millions of people look over the internet to know about the local and global weather and also weather hazards. All are curious about whether umbrella is required today or whether this weekend's big game is going to be spoiled by rain or not.

If you stay on the Earth, weather is bound to affect you in diverse ways. The kind of house you stay in, the type of clothes you were, even the type of leisure activities and games you enjoy - all are determined by the weather.

Weather influences the nature of the soil on which we live. Even plants and animals adapt to various living conditions due to weather variations. Depending on their surrounding weather, plants adapt to survive in extreme dry or wet conditions. The shapes of their branches also depend on the prevailing weather. Similarly, the animals also get acclimatized to endure the extremities of their natural habitat.

Even though we cannot 'do' much regarding the weather conditions, our meticulous study about the weather helps sharpen our ability to predict the approaching weather conditions. The ability to accurately foresee the oncoming adverse weather conditions help to reduce the loss to the farmers as they can modify their farming practices according to the predicted weather.

Weather conditions vary depending on the form of the atmosphere of the earth. A feature unique to the atmosphere that surrounds our world is that it contains water vapor, and a temperature that maintains this water in three different forms - solid, liquid and gas.

Technically, the day to day changes in the atmosphere conditions is referred to as the weather. Different aspects of weather like the windspeed, humidity, temperature, type and amount of precipitation etc. are measured to give us an idea of what kind of conditions we face on earth.

The sun causes these atmospheric variations and determines the condition of the atmosphere based on the location on the globe. The temperature rises up and falls down faster in land areas than oceans. The Polar Regions receive less intense radiation from the sun than the equatorial regions.

The atmosphere is a massive complex phenomenon that wants to maintain an equilibrium of its own, in the same way like every other complicated systems. The cooler regions around the poles of the earth suck in the warm air from the equatorial regions. The rotation of the earth and the friction with the land also determines the movement of air. This whole system is contained within a small area by the gravity of the earth.

Complex patterns of low and high air pressure are caused because of the combination of a variety of factors like the geography of Alicante and Benidorm in Spain, the uneven heating, balancing force of the earth to even out the irregularities, and the gravitational and rotational forces. Different weather conditions are produced as result of interaction between these low and high air pressures with the ground.
Being very passionate about Costa Calida and Alicante, Ray Walberg is writing countless long articles on this specific topic. Writing for publications on Alicante and pictures of benidorm spain the writer expressed his capability on the subject.

Article Source: http://EzineArticles.com/?expert=Ray_L._Walberg

Cherie and Nicole :)

External forces that can modify landforms

Crustal movements lead to the formation of landforms like volcanoes and plateaux on the Earth's surface. Theses lanforms are constantly changing , with new landforms being created and others destroyed. These are a few reasons that lead to changing landforms:

WEATHERING
Weathering is a process by which rocks are progressively broken down into fragments where they are. Weathering can be caused by changes in temperature, action of water and action of plants.

LARGE CHANGES IN TEMPERTURE
Large changes in temperature can cause weathering. For example in the desert, the hot sun heats up the surface of the rock during the day and causes the surface area to expand. However, the inside of the rock remains cool as rocks are poor conductors of heat. At night, the atmospheric air temperature drops. The surface layer cools and contracts fater than the inside of the rock. This constant expansion and contraction weakens the rock's surface layer. If water is present, the rock will crack and the surface layer will break off in layers or into small pieces.

ACTION OF WATER
Water is also an important agent in weathering. Rainwater combines with carbon dioxide in the air to form carbonic acid which dissolves certain types of rocks such as limestone(soft rock). When acidic rainwater seeps into cracks in the limstone, it dissolves parts of the rocks. Over time, the acid can wear down enough limestone rocks to form landforms such as caves.

ACTION OF FREEZING WATER
ON a high mountain, water from melting snow or rain may enter cracks in rocks. At night, when the temperature falls below 0 degrees celsius, the water turns into ice. When the water freezes, it expands and causes the cracks in the rock to widen. During the day, when the temperature rises, the ice melts. This alternate freezing of water and melting of ice causes the cracks to become wider, eventually breaking the rocks apart.

PLANT GROWTH
Weathering can also be caused by plants. For example, teh wind may deposit seeds into the cracks of rocks. As the seeds grow into plants, the roots grow into the rocks and force the cracks in the rocks to penetrate concrete and cause cracks in pavements.

EROSION
Unlike weathering which breaks down rocks into fragments where they are, erosion is the process of wearing down surface materials and moving them from one place to another. Erosion is caused mainly by moving water, waves and wind.

ACTION OF RUNNING WATER
Water in streams and rivers carry a lot of sediments, or small paricles such as silt, fine sand and mud. As this water flows over rocks, it wears down the rocks in its path. The sediments in the water act like sandpaper, scraping and wearing away the rocks. Over time, the action of the water and the sediments it carries gradually erode the Earth's surface.

ACTION OF WAVES
Waves are powerful agents of erosion. The constant breaking down of waves against the shore, togother with the grinding action of sand and stonescarries in the waves, erodes the sashore to produce sandy beaches, caves and cliffs.

ACTION OF WIND
Wind erosion is common in dry areas where there are few plants to hold the soil or othere loose weathered materials in its place. In deserts, strong wings can carry large amounts of sand and wear away the surfaces of rocks in their paths. The sand polishes and smoothens the surface of these rocks. As sand is heavy, it cannot be blown very high into the air. Hence, erosion tends to take place mainly at the base of rocks.

Sources: our textbook
Cherie and Nicole :)

Sunday, July 10, 2011

Weather and Climate

(http://www.nasa.gov/mission_pages/noaa-n/climate/climate_weather.html)
Weather is basically the way the atmosphere is behaving, mainly with respect to its effects upon life and human activities. The difference between weather and climate is that weather consists of the short-term (minutes to months) changes in the atmosphere. Most people think of weather in terms of temperature, humidity, precipitation, cloudiness, brightness, visibility, wind, and atmospheric pressure, as in high and low pressure.

In most places, weather can change from minute-to-minute, hour-to-hour, day-to-day, and season-to-season. Climate, however, is the average of weather over time and space. An easy way to remember the difference is that climate is what you expect, like a very hot summer, and weather is what you get, like a hot day with pop-up thunderstorms.

The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere "behaves" over relatively long periods of time.

When we talk about climate change, we talk about changes in long-term averages of daily weather. Today, children always hear stories from their parents and grandparents about how snow was always piled up to their waists as they trudged off to school. Children today in most areas of the country haven't experienced those kinds of dreadful snow-packed winters, except for the Northeastern U.S. in January 2005. The change in recent winter snows indicate that the climate has changed since their parents were young.

If summers seem hotter lately, then the recent climate may have changed. In various parts of the world, some people have even noticed that springtime comes earlier now than it did 30 years ago. An earlier springtime is indicative of a possible change in the climate.
 
The weather is made up of different elements, which are measured either by special instruments or are observed by a meteorologist. These measurements are then recorded and used in the making of climate graphs and weather forecasts. The table below shows the weather element details:

ElementDescriptionHow it is measuredUnits of measurement
PrecipitationMoisture from the sky e.g. rain, snow etc.By a Rain GaugeMillimetres (mm.)
TemperatureHow hot or cold it isBy Thermometers, found inside a Stevenson ScreenDegrees celsius ( c)
Wind SpeedHow fast the wind is blowingBy an AnemometerKnots, or by the Beaufort Scale
Wind DirectionWhere the wind is blowing fromBy a Wind VanePoints of the compass (north, north-west etc), or bearing in degrees
ElementDescriptionHow it is measuredUnits of measurement
HumidityThe amount of water vapour in the airBy a Hygrometer (wet and Dry Bulb Thermometers)Relative Humidity (% of water vapour that can be held by the air at the actual temperature)
Air PressureThe "weight" of the air pushing on the surface of the EarthBy a BarometerHectopascals (although most people know it as millibars)
Cloud CoverThe amount of cloud in the skyIt is observed by a meteorologistOktas - eighths of the sky
VisibilityHow far you can seeIt is observed by a meteorologistKilometres
SunshineThe hours of sunshineBy a Sunshine RecorderHours and minutes
ElementDescriptionHow it is measuredUnits of measurement

(http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/climate_systems/elements_of_climate.html)

The Elements of Climate

Climatology is the study of the long-term state of the atmosphere, or climate. The long-term state of the atmosphere is a function of a variety of interacting elements. They are:
  • Solar radiation
  • Air masses
  • Pressure systems (and cyclone belts)
  • Ocean Currents 
  • Topography

Solar radiation

Solar radiation is probably the most important element of climate. Solar radiation first and foremost heats the Earth's surface which in turn determines the temperature of the air above. The receipt of solar radiation drives evaporation, so long as there is water available. Heating of the air determines its stability, which affects cloud development and precipitation. Unequal heating of the Earth's surface creates pressure gradients that result in wind. So you see, just about all the characteristics of climate can be traced back to the receipt of solar radiation.

Air masses

Air masses as an element of climate subsumes the characteristics of temperature, humidity, and stability. Location relative to source regions of air masses in part determines the variation of the day-to-day weather and long-term climate of a place. For instance, the stormy climate of the midlatitudes is a product of lying in the boundary zone of greatly contrasting air masses called the polar front.

Pressure systems

Pressure systems have a direct impact on the precipitation characteristics of different climate regions. In general, places dominated by low pressure tend to be moist, while those dominated by high pressure are dry. The seasonality of precipitation is affected by the seasonal movement of global and regional pressure systems. Climates located at 10o to 15o of latitude experience a significant wet period when dominated by the Intertropical Convergence Zone and a dry period when the Subtropical High moves into this region. Likewise, the climate of Asia is impacted by the annual fluctuation of wind direction due to the monsoon. Pressure dominance also affects the receipt of solar radiation. Places dominated by high pressure tend to lack cloud cover and hence receive significant amounts of sunshine, especially in the low latitudes. 

Ocean Currents

Ocean currents greatly affect the temperature and precipitation of a climate. Those climates bordering cold currents tend to be drier as the cold ocean water helps stabilize the air and inhibit cloud formation and precipitation. Air traveling over cold ocean currents lose energy to the water and thus moderate the temperature of nearby coastal locations. Air masses traveling over warm ocean currents promote instability and precipitation. Additionally, the warm ocean water keeps air temperatures somewhat warmer than locations just inland from the coast during the winter.

Topography

Topography affects climate in a variety of ways. The orientation of mountains to the prevailing wind affects precipitation. Windward slopes, those facing into the wind, experience more precipitation due to orographic uplift of the air. Leeward sides of mountains are in the rain shadow and thus receive less precipitation. Air temperatures are affected by slope and orientation as slopes facing into the Sun will be warmer than those facing away. Temperature also decreases as one moves toward higher elevations. Mountains have nearly the same affect as latitude does on climate. On tall mountains a zonation of climate occurs as you move towards higher elevation.

Cherie and Nicole :)