GMK Physical Geography Slides

GMK PHYSICAL GEO SLIDES are now available in YouTube for high quality presentation notes on physical geography. Here are some links. Remember to view, like and subscribe for more content.
Links
https://youtu.be/8UuWjdE56mU
https://youtu.be/dQV1Zsi251s
https://youtu.be/ouv2YZ7NRA0
https://youtu.be/M84VF4zMndo

CONTINENTAL DRIFT THEORY In this video there is a detailed description of the Continental Drift Theory. The video is a good source of highly summarized notes for quick and easier rev...

ARE YOU A STUDENT WONDERING HOW YOU CAN LEARN OR HAVE ACCESS TO GEOGRAPHY LEARNING MATERIALS. I HAVE GOOD NEWS FOR YOU. CLICK ON THE LINKS BELOW FOR COMPREHENSIVE PHYSICAL GEOGRAPHY NOTES. THE RULE IS SIMPLE-CLICK THE LINK-SIGN UP-AND SUBSCRIBE FOR MORE NOTES AND VIDEOS. WELCOME.
https://youtu.be/RHSCuqapxcg
https://youtu.be/7ek7Jf5RyCo
https://youtu.be/5QewjcN-_gw
https://youtu.be/ZJveJhFlcL0
https://youtu.be/utfsbDgLRGI
https://youtu.be/V_ujMiMJ_fg

VEGETATION I INTRODUCTION AND KENYA’S VEGETATION ZONES The video is focusing on various vegetation zones in Kenya, their location, characteristics, and examples.

DIFFERENCES BETWEEN BASIC LAVA AND ACIDIC LAVA
BASIC LAVA
i) Has lower silica content (45 – 55 %)
ii) High amount of basic oxides (over 55%)
iii) Has low viscosity/ highly fluid
iv) Cools and solidify slowly due to low viscosity
v) Has low viscosity
vi) Has low density
vii) Has less feldspar and quartz
viii) Comes out in a quiet eruption
ix) Erupts frequently
x) Form basic rocks which are dark in colour
xi) Flow for longer distances/ spreads widely
xii) Piles up to form low and gently sloping volcanoes on the surface
ACIDIC LAVA
i) High percentage of silica (over 65%)
ii) Low amount of basic oxides (less than 35%)
iii) Highly viscous or molten/ very thick/very sticky
iv) Cools and solidifies quickly/ faster due to high viscosity
v) Has high viscosity
vi) Has a higher density
vii) Has more feldspar and quartz
viii) Comes out in a violent eruption
ix) Takes time before erupting
x) Form acidic rocks which are light in colour
xi) Flow for short distances/spreads narrowly
xii) Piles up to form high and steep volcanoes on the surface

Characteristics of ITCZ
1.It is found within latitudes 231/2°N and 231/2°S of the equator
2.It has low pressure and doldrums (light winds).
3.It has high temperatures due to the overhead sun.
4.SE & NE trade winds converge/ meet here.
5.It is associated with convectional rainfall and thunderstorms/ receives high rainfall.
6.It migrates N or S of the equator with the apparent movement of the overhead sun.

FACTORS INFLUENCING WIND DIRECTION AND SPEED
1. Pressure gradient – wind blow from high to low pressure areas. The higher/ steeper the pressure gradient between two places the faster the wind blows and the smaller/ gentler the pressure gradient between two places the gentler the wind blows.
2. Coriolis force – it is a force which causes deflection of wind to the right in the northern hemisphere and to the left in the southern hemisphere due to the rotation of the earth.
3. Centrifugal force – in the northern hemisphere winds move in clockwise direction in anticyclones and anticlockwise in cyclones while in the southern hemisphere winds move in anticlockwise direction in anticyclones and clockwise in cyclones.
4. Effects of friction –presence of obstacles like trees and ruggedness of the earth’s surface create friction on moving air thus causing it to reduce its speed thus lose its strength. Also the wind can also change course when its path is blocked.

SEA BREEZE
They are cool winds blowing from the sea to the land during the day.
Characteristics of the sea breeze
i) It is cool/ cold.
ii) It occurs during the day.
iii) It blows from the sea to the land.
iv) It affects small regions of land bordering a sea or large inland lakes.
Formation/ occurrence of a sea breeze
 During the day land is heated faster than the sea.
 Warm less dense/ light air over the land rises creating a low pressure zone.
 The sea is heated slowly and has dense cool air thus creating a high pressure zone.
 Therefore the cool dense air from the sea blows towards the land to replace the warm rising air.
 This cool air from the sea to the land is called the sea breeze.
 The rising air over the land cools and flows towards the sea at high altitude and eventually descends over the sea as cool air to replace the one that is flowing towards the land. The circulation continues until it is reversed at night.
LAND BREEZE
They are cool winds blowing from the land to the sea at night.
Characteristics of the land breeze
i) It is cool/ cold.
ii) It occurs at night.
iii) It blows from the land to the sea.
iv) It affects small regions of land bordering a sea or large inland lakes.
Formation/ occurrence of a sea breeze
 At night the land loses heat faster than the sea.
 The cool dense air over the land creates a high pressure zone.
 The air over the sea is warm and less dense/ light and therefore it rises thus creating a low pressure zone over the sea
 Therefore the cool dense air from the land blows towards the sea to replace the warm rising air.
 This cool air from the land to the sea is called the land breeze.
 The rising warm air from the sea advances towards the land at high altitude and eventually descends over the land to replace the one which is flowing towards the sea. The circulation continues until the pressure difference is reversed during daytime.

For physical Geography notes videos, check in the youtube channel "PHYSICAL GEOGRAPHY NOTES FINEST FOR HIGH SCHOOL' and subscribe.

How the nebula cloud theory formed the earth
 There was a huge cloud of dust, ice particles and gases like hydrogen and helium called nebula.
 This cloud whirled and rotated at high speed.
 The materials cooled and condensed into a disc shape.
 There was gravitational attraction within the materials causing the particles to be compact.
 Particles at the centre of the disc formed the sun.
 Some particles broke off from the edge of the disc.
 The particles rotated/ whirled faster towards the centre of the disc in different directions.
 As they rotated they cooled and solidified to form the planets.
 They bumped into each other and were set in their orbits round the sun by the gravitational attraction.
 The earth is one of the planets which were formed.
Weaknesses of the Nebula cloud theory
i) Cause of the rotating was not explained.
ii) Origin of the nebula was not explained.
iii) All planets should rotate in the direction of the nebula in anticlockwise direction but Venus and Uranus rotate in clockwise direction

How the passing star theory formed the earth
 The sun existed earlier than the planets.
 A big star with a higher/ greater gravitational pull passed near the sun.
 The star pulled large volumes of gas materials from the sun.
 The gas materials exploded and split into portions which cooled and condensed to form planets.
 The planets were then set on their orbits around the sun.
 The earth is one of the planets which were formed.
 Smaller gas materials formed heavenly bodies which were also set on their orbits.
 During the cooling, semi liquid dense materials collected at the centre to form the core of the earth.
 Less dense materials cooled around the core to form the mantle.
 Lightest materials formed around the mantle to form the crust.
Weaknesses of the passing star theory
i) Chances of another star passing near the sun are rare/ nil/ slim.
ii) Origin of the sun/ star is not explained.
iii) The hot gas materials should have dispersed rather than condense.
iv) The materials should have followed the star as it had greater gravitational pull.
v) Effect of the star setting planets on their orbits would have reduced as the star.
vi) The gases would have followed the star since it had a greater gravitational pull.