Campaigners on important but complex issues, annoyed by the length of time required for public deliberations, often react by exaggerating their claims, hoping to force a single solution to the forefront of public debate. But however well intentioned, scaring the public into a predetermined solution often backfires: when people realise that they have been misled, they lose confidence and interest.
Last month, there were two examples of this in a single week. On September 19, the French researcher Gilles-Eric Séralini attempted to fuel public opposition to genetically modified foods by showing the public how GM corn, with and without the pesticide Roundup, caused huge tumours and early death in 200 rats that had consumed it for more than two years.
Supplying an abundance of pictures of rats with tumours the size of ping-pong balls, Mr Séralini certainly captured the public's attention. But his research posed many problematic issues. For starters, the Sprague-Dawley strain of rats that he used is naturally prone to tumours. Studies of these rats show that 88 to 96 per cent of those that serve as experimental controls develop tumours before they reach 2 years of age.
But the public saw only pictures of tumorous rats that had consumed GM corn and Roundup. If the public had seen the similarly grotesque tumours that grow on untreated rats, officials most likely would not have acted so hastily.
Moreover, Mr Séralini's results contradict the latest meta-study of 24 long-term studies, which found that the data do "not suggest any health hazards" and display "no statistically significant differences" between GM and conventional food.
The European Food Safety Authority has now concluded that the "design, reporting, and analysis of the study, as outlined in the paper, are inadequate".
The study was partly funded by Criigen, a group that campaigns against biotechnology. Criigen's scientific board is headed by none other than Mr Séralini, who has also just released a book (in French) and a documentary film decrying GM food.
This debacle matters because many GM crops provide tangible benefits for people and the environment. They enable farmers to produce higher yields with fewer inputs (such as pesticides), so that more food can be produced from existing farmland.
The Séralini fiasco was only a week old when the Climate Vulnerability Forum, a group of countries led by Bangladesh, launched the second edition of its Global Vulnerability Monitor. Headlines about the launch were alarming: over the next 18 years, global warming would kill 100 million people and cost the economy upwards of US$6.7 trillion (Dh24.61tn) annually.
These public messages were highly misleading - and clearly intended to shock and disturb. The majority of deaths discussed in the report did not result from global warming. Outdoor air pollution - caused by fossil-fuel combustion, not by global warming - contributed to 30 per cent of all deaths cited in the study. And 60 per cent of the total deaths reflect the burning of biomass for cooking and heating, which has no relation to either fossil fuels or global warming.
The technologies that can really make a difference quickly and at lower cost are scrubbers that clean smokestack emissions, catalytic converters that reduce tailpipe emissions and many others. By focusing purely on cutting CO2, we neglect to help many more people.
Likewise, overcoming the burden of indoor air pollution will happen only when people can use kerosene, propane and grid-based electricity. If the Global Vulnerability Monitor's recommendation to cut back on fossil fuels were taken seriously, the result would be slower economic growth and continued reliance on dung, cardboard and other low-grade fuels, thereby prolonging the suffering that results from indoor air pollution.
When confronted with their exaggerations, the authors claimed that "if you reduce hazardous air pollution, it is difficult to not also reduce warming emissions".
But for both indoor and outdoor air pollution, the opposite is more likely true: lower carbon emissions would mean more air pollution deaths.
When scare tactics replace scientific debate, whether about GM crops or climate change, nothing good can come of it. We all deserve better.
* Project Syndicate