class test - temperature answers

1	(a)	City Latitude Altitude Mean annual temperature Santiago (Chile) 33°27′S 520 metres 18°C Sydney (Australia) 33°52′S 110 metres 32°C
		Table 1
		With reference to Table 1, explain why Santiago and Sydney experiences different temperatures.                                                                                                                   [4] -        While both places are located at a similar latitude, Santiago is located at higher altitude of 520m as compared with Sydney which is located at lower altitude of 110m. -        At lower altitude, there is more long wave radiation as heat is absorbed by the earth near the ground surface, which results in higher temperatures. -        Whereas at higher altitude, there is lesser longwave radiation as the air is less dense, resulting in lower temperatures. -        This accounts for Chile experiencing a lower mean annual temperature which is 14°C less than Sydney. Remarks : Most students didnt explain about longwave radiation. Some mention that it is due to distance from the sea (But the question did not provide any evidence to sea, so DO NOT blindly memorize and regurgitate from the text book!). Also need to provide data from the Table 1 eg 520m in altitude. Some students do not understand what 'Altitude' means and think that is the distance to the sea. Altitude means height of a place!
	(b)	State the difference between the terms “Weather” and “Climate”.                                 [2]                             -        Weather refers to the atmospheric condition of a place at a specific time. -        Climate refer to the atmospheric condition of a place over a long period of time, usually over 30 years.   Remarks : A few did not wrote '30 years'. Weather is NOT only about TEMPERATURE.  Perfect ans: Armin, Chikin
	(c)	(i) What does the instrument in Fig. 1 measures?  What does the instrument in Fig. 1 measure if it is placed in the field for a duration of 24 hours?                                           [1]                                                                                                                                                                    Maximum and Minimum Temperature  Remarks: Some wrote sling psychrometer/Relative humidity! Its not the same!
		(ii) State 3 factors that may cause inaccurate data to be collected from the instrument. [3] -        Parallax error while reading off the thermometer -        Placement of thermometer under direct sunlight/ too near to the ground may cause heat radiated from the ground that will affect the reading -        The instrument may be left in the field for a long period of time which cause results recorded to be in accurate - The instrument may have been faulty and thus affect the readings. Remarks : Some students confuse the thermometer with the sling psychrometer and thus provided answers such as 'holding it too close to the body', 'swinging it at inconsistent speed' Accept any other possible answers.
	(d)	Months Temperature January 28.9 °C February 29.3°C March 29.5°C April 31.7°C May 29.9°C June 31.5°C July 32.0°C August 32.5°C September 32.9°C October 33.6°C November 32.0°C December 30.5°C Fig. 2
		(i) Calculate the mean temperature of Country X.                                                           [1]     (Total) / 12 = 31.2°C
		(ii) Calculate the temperature range of Country X.                                                         [1]       33.6°C – 28.9°C = 4.7°C Remarks : Many did not show anwers for (ii) after the calcuation. wrong units will minus half a mark.
	(e)	Describe and explain the characteristics of the Stevenson screen.                                 [3]                                                                                                                   -        White/wooden: Insulate against heat so that temperature is regulated -        Window panels/louvred sides : For ventilation -        1.5m away from the ground : To keep away from the ground as it absorbs heat