The reality is China and Hong Kong have the opportunity to show the world how progressive the SAR and central government can be.

Sticking to the rule of law, the values of an open market and the principles of true democracy would not only be a feather in the cap of our communist overlords but also show the rest of Asia that Hong Kong is here to stay and ready to play by the same rules as the rest of the democratic world.

I refer to the front-page report ("Winners and losers as ad spend up 65pc in 5 years", November 18).

The figures you quote for TVB Jade, "HK$12.3 billion in 2008 to HK$14.6 billion last year" could not be further from the truth. It seems that some people have been peddling similar figures in their attempt to portray a very large and growing pie of advertising spending in the free television market.

Television Broadcasts Limited (TVB) is a listed company. Its financial information is published in annual reports, which are available on TVB and Hong Kong Exchanges and Clearing websites.

For the record, the total turnover for TVB in 2008 was HK$4.407 billion, of which HK$2.346 billion was from Hong Kong television broadcasting. The total turnover for 2012 was HK$5.448 billion, of which HK$3.167 billion was from Hong Kong television broadcasting.

It is incorrect to suggest the ad revenue for Jade channel was HK$12.3 billion in 2008 and HK$14.6 billion in 2012.

I refer to the report ("UN climate chief Christiana Figueres says coal industry must transform", November 19).

It made no sense for UN climate chief Christiana Figueres to tell delegates at a conference organised by the World Coal Association "that further capital expenditures on coal can go ahead only if they are compatible with the 2 degrees Celsius limit".

Humanity cannot control the climate of planet earth as if we had a giant thermostat. Climate has always changed naturally, and always will, no matter what we do.

Some scientists say we are heading for dangerous warming because of carbon dioxide (CO₂) emissions from coal combustion and other industrial activities. Others, such as Russian solar experts, believe that we are in for far more dangerous cooling as the sun moves into a prolonged weak phase over the coming decades. If that is true, then our addition of CO₂, if it has a significant effect, may very well help delay the next ice age.

The truth is, we simply do not know. Trying to unravel the causes and consequences of climate change is arguably the most complex science ever tackled. Professors Chris Essex (University of Western Ontario, Canada) and Ross McKitrick (University of Guelph, Canada) write in their book , that climate "is one of the most challenging open problems in modern science. Some knowledgeable scientists believe that the climate problem can never be solved."

Yet, on this weak basis, Figueres essentially wants the world to stop burning coal, our most abundant and least expensive power source. That electricity prices would probably soar and millions of jobs would be lost seems to have no influence on her. Saving the climate trumps everything else.

The only way to effectively counter this is to show that there is no climate crisis: it has not warmed as activists feared, there has been no overall increase in extreme weather, polar bears are doing fine, and the sea level rise is not accelerating.

If people like Milton Catelin, CEO of the World Coal Association, lack the courage to bring this up, then the world will soon follow us here in Ontario, where frightened coal supporters let the industry die rather than risk controversy.

Tom Harris, executive director, International Climate Science Coalition, Ottawa, Ontario, Canada

Although it has been discussed for a number of years, the government has, until now, failed to push through a waste charging scheme in Hong Kong. In the meantime, the problem of waste volume has got worse.

A survey in September revealed that, if such a scheme was in place, most people would prefer to buy refuse bags from the authorities, which would limit the quantity of refuse they can dispose of.

Whatever option is adopted, it will definitely increase the expenditure of households. Some middle-class citizens have already been affected by inflation and there are many families living below the poverty line. This charge will add to their financial burden.

These families probably generate less waste than other households so it would be unfair if a building-based charge was imposed.

I also don't think the charge scheme will get to the root of the problem, although I admit it is preferable to expanding landfills or building an incinerator.

What has to be done is to raise the public's level of awareness so people appreciate the need to be environmentally friendly. If there is this shift in attitudes, then waste can be reduced at source.

My further concern relates to privacy.

It has been suggested that surveillance cameras might have to be used to check on residents who simply discard the rubbish rather than paying the charge. There will have to be a great deal more discussion of the various proposals for the waste charging scheme.

I applaud the positive intent in M. L. Fong's letter ("Acting to solve scourge of ethnic bias", November 23) in wanting to showcase Chinese interacting with people from ethnic minorities in local entertainment productions.

The purpose is to enhance perceptions and perspectives. However, sadly, a problem with local drama series and films is that, whenever a non-Chinese character is involved, the depiction normally reinforces stereotypes, and is often negative.

I cannot imagine a local production showing a Filipina as a doctor or senior ward nurse, or a Nepali as an architect or engineer. Ethnic minorities are never portrayed in positions of authority or responsibility, and discrimination is rife in Hong Kong.