1969-04-05 — Page 15

★款僑華真三節張四第

Br+AZEECER WAH KIU YAT PO

郭日僑華

六期星一日五月四年九六九一窩公年八十五鲴民中

(接第四張第二頁)

営

僑 業

RADIOZÓN DE

(+-)

·林錫衡

1969PFUM

地理科 (廿二)

·劉玉精、

A weather station contains the following

instruments: maximum and minimum thermometer,

anemometer and wind vane; and radiosonde. For anët of them:

(*) describe its appearançe

(b) explain how it is used to obtain weather,

records.

Hur man and minimum thermenster

A maximum thermometer is like a common mercury thermometer and there is an iron index above the head of the colum of mercury.!

It is usually placed horizontally and is used to record the maximum temperature of a day. Nhan tho tümperature rises the mercury expands and pushes the index along the tube, When the temperature falls the mereury contracts and the index remains behind. The mkachaam temperatura is obtained by reading the sõale the end of the index which is in contact with the mercury. To prepare the instrument for measuring the maximum temperature of the following day the index is drawn by a magnet back to the mercury head.

AS MAXINUM: THERMOMETER

PORTAL - MON

30 20 30 M2 24 mo

A minimum thermometer is like a common #leona) thermometer, but with an index inside the liquid.

De It is used to record the minimum temperature of the day. When temperature rises the alcohol expands passing the index which does not more. When tempereture falls the alcohol contracts and the surface tension of ite miniscus pulls the index along the tubs. The minimum temperature is obtained by reading the sea le at the end of the Indar which is near to the miniscus.

A Miximus TERAMONETER

Paraaut.]

REFLECTOR

[ali (a) With the aid of diagram explain the formation of (1) relief rain (44) radiation for (111) thunderstorm

\\(b); Nemo (1) a region in temperate latitule where

grain falls all the year round

(11) a region where rain falla from June www to September

(115) à regiòn where rain rarely falla

(jv) a region where rain falle in winte write brief explanatory notes on each.

When the moist onshera Wind BLOWS against relief barrior, air is forded to rise. The atmospheric pressure in the air decreases with the result that it expanda. Consequently its temperature falls. This means that the capacity of the air for holding water vapour", decreases. The ratio of the total vapour content to the saturation value therefore increases 1.e. the relative humidity increases." When the R.H. reaches 100% air is saturated but expansion and cooling continue. Further cooling will produce condensation i.e. some of the

pour will change into liquid water. Thesa tiny droplets form clouds As a result of coalescence and collision, large drops cams into being. When their weights are sufficient to carry them downward through the atmospher which continually axert resistence to the motion they drop as rain.

FORMATION OF RELIEF TRAIN

九六九巿中文中學會考試題 化學科

分别配成溶液然後加入稀硫酸若不生 氧体的是硫酸鎂另二者生氧体將所生 氧体通入醋酸鉛溶液茗生黑色沉澱則 誘氧体果硫化物毘硫化鎖不生累 色沉澱的是二氧化硫原物是亞硫酸鎂

MgS + H2SO4 → MgSO4 + H2 S ↑

\ H1S + (CH2 COO), Pb → 2 CH2 COOH-

MgSOut Ha

Mg S Qs + Hz SQu

MgSOμ+ H2O + SO T

SQ 4 CH5000), Pb → K

(4)硝酸鈉亞硝酸鈉鑑別法

分別加醋酸生紅棕色氯体的是亚硝酸

N&NO2+ CH3COOH → CH, COONa + HNO2

ZHNG → HO+ NOT ↑ NOT (##2,

NING LCH COOH – CH COONG - ANGI

(5)硫酸苙酸硝酸鑑到法

分別加硝酸鋼溶液 生白色沉澱的原物 是硫酸其餘二者不生沉澱

H2SOμ+ Bæ (NO3)2 → 2 HNO + BASOμl).

餘下二者募取原液加硝酸銀溶液若生 白色沉澱此沉澱見光變紫灰色,不溶於 硝酸但溶於氨水則原液是接酸不生說 澱的是硝酸.

HCI + AgNO3 → HNO2+ A9CIV)

ZAGCi¬2Ag↓ + Chat

AgCl + 2NH4OH →→ Ag(NH3), CI + 210

FORMATION

FIONDER 570R M

CLOUD

32F

RELER BARRIER

From the maximum and minimum temperature of the a

day we can get i

The mean daily range – obtained as an average of the two values

daily (diurnal) range – obtained as the différence: of the two temperatures..

Wind vans and anemome

namometer

A wind vane consists or a freely moving horizontal) sra (in the form or an arrow), and below, a fixed framework indicating the four cardinal points of the

The direction of wind is obtained by looking at the way in which the arrow is pointing.

The revolving cup anemometer consisting of three metal hemisphere is used to measure wind speed.

The wind pressure on the concave side of the cup is greater than on the convex aide. This causes them to spin round the vertical axis. The rate of rotation increases with wind speed. The vertical axia connects with a box containing a mechanism which establishes a contact when the cups, have rotated a certain number of times. These contacts are recorded on a piece of paper of a drum which is rotated by a clook.

These instruments are erected on the top of a building and at least 20 feet high above the neighbouring building or trees. Wind speed is measuret in knots; 1 knot means 1 nautical wile per hour.

THE REVOLYING CUPS

(11) Radiation For

"It is formed when the ground is cooled by radiation at night. Its forkation is confined to. ground surface since the daily variation in sea surface temperature does not ordinarily become sufficient to cool the lower layer of the air to its dew point. By direct conduction and radiation, the cool land surface cools the Lower layer of the air. Provided that the temperature of air is reduced to below its de point, condensation will occur at ground level Necessary conditions:-

1. Cloudless sky to permit fraë radiation 2. Sufficient moisture in the air so that little cooling is enough to produce condensation

light wind so that cooling will be spread upward by slight turbulance in the air.

OF RADIATION FOO

FORMATION

CLEAK EKT

・MOIST BIR

WIND

RADIATION

ENDING.

PONTIVE CHANGE

((b) (1) Pacific coast of Canada

This part lies in the belt of the onsho wasterlies which on blowing against the mountain slopes give orographic rain to the coastal side of the mountains. Besides, depressions formed over the Pacific along tim Polar Front moving eastwards are also responsible for bringing rainfall all the year round to this part of Canada,

(11) Burman

From June to September it is under the influence of the onshere south-west monsoon which brings rain. In the other season, it is under the influence of the dry off-shor north-east monsoon which brings very little rain

(111) Atacama Desert

It lies in the belt of offshore trade wind belt. In this region South-East Trade Wir blows all the year round and therefore there is little rain throughout the year.

Vaub

OF AN AKEMON TER

GROUND

COOLT

Radioz onde

A radiozonde consists of a balloon attached below. which is a parachute and a light-weight box in whicr Instruments are put.

- it is used to measure the weather condition or itha upper air. Inside the light-weight box are a

small aneroid barometer, a bimetallic thermometer

■ hair hygrometer. They are attached to a tiny transmitter with batteries supplying the power.

radiozonde up in the air and it drifts with wind. The radio sender connects the instruments and sends signala to the ground thus reporting the pressure, temperature and humidity at frequent intervals, Usually the ballon carries a reflector so that a radar set can determine. ita asimuth and elevation angle.

When the balloon is released, if bringa NAS

111). Thunderstorm

A thunderstorm is a local storm characterised by the presence of lightning and thunder. It is caused by intensively powerful up-currents of air dcouring within dense moist cumulonimbus clouds which themselves result from great atmospheric instability, As, the b reated air rises the subsequent processes ar~ decreasing pressure, further expansion saturation, further cooling, condensation ang lastly precipitation.

Precipitation from the storm la characteristically heavy and composed of lary drops of rain. If the vigorous convection. current have sufficient force to go well abova the freezing point, hail will fall from the aloud.

Lightning is the result from the splatting up of raindrops and the consequent development of strong charges of static electricity in the rapidly ascending air currents./

Thunder is produced by the violent expansion of air caused by the tremendous heat af lightning.

(iv) California

It lies between the Westerly and Trade kind belts, Due to the shifting of the wind. belts, in winter (Uct-March) it is under the onshore westerly winds which bring rain to the area. Summer is dry because it is affected by the offshore north-easterly winds.

Questions for next week!

Write an explanatory account on the formation) of each of the following:

1. Trade winds and westerly winds.

2. Chinook

What is meant by the swing of the wind systems Explain how it affects the climate of South- Western Australia.

43. On a sketch map of the world locate examples of

the following

(a) an equatorial fores

(b) a tropical monsoon forest

(c) a temperate grasslan

(d) a tropical desert

For each of the above, deactive ne characteristic features of the vegetation thereis and show how they are related to the climate of the region.

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