On Monday at the UN Climate Summit in Paris, Canada made a decision that shocked and confused many in the policy world.

Environment Minister Catherine McKenna stated that Canada backs the idea of eventually limiting global warming to less than 1.5 °C above pre-industrial levels. This lower temperature limit is advocated by many developing countries, including low-lying small island states like Kiribati, the Marshall Islands, and Tuvalu.

From a numbers standpoint, Canada’s new position may look crazy. The lower temperature target appears, practically speaking, next to impossible to achieve.

The world is currently far off the pace to stay within the existing 2 °C limit agreed upon by most of the major world economies, including our neighbour to the south. If you add up all of the emissions reduction pledges made by the different countries meeting in Paris, the world is on pace to warm by as much as 3.5 °C or more.

To have a good chance of staying within the 1.5 °C limit, the world can only emit another 270 gigatons of carbon dioxide. At the current rate of emissions, we’ll blow that entire bank in less than a decade. Then, the only way to keep within the target will be to rely on what scientists call “negative emissions” – to suck carbon dioxide out of the air, using technologies that either do not yet exist, are unproven, or have never been implemented at large-scale.

Is this yet another case of Canada’s rhetoric on climate action being unmoored from the reality of greenhouse gas emissions?

In fact, the decision is about respect. In pushing to include reference to a 1.5 °C limit, Canada is saying that the people of small island developing states and vulnerable countries like Bangladesh matter.

Despite what you’ve probably heard, the popular 2 °C target is not dictated by science. The 2 °C target is a political decision made largely by the developed countries – the same countries that are most responsible for climate change.

The fact is that there is no scientifically definable “safe” amount of climate change. Science can provide us with a guide to the impacts of different levels of warming. The amount of warming we deem as “safe,” however, depends on our values and our perception of risk.

If you live in a small island nation in the tropics, more than 1.5 °C – not 2 °C – of global warming certainly seems dangerous.

For example, with more than 1 m of sea-level rise, around 90% of countries like Tuvalu, the Marshall Islands, and Kiribati could become so prone to flooding as to be uninhabitable. While there’s large uncertainty about the rate of future sea-level rise, evidence from the distant past suggests the risk of losing the major ice sheets increases sharply with more than 1.5 °C of warming.

There’s arguably even greater concern among larger island countries like Fiji about coral reefs, a key source of food, income, and coastal protection in small island countries. The world’s coral reefs are already in trouble due to warming and acidifying ocean waters. If warming can be kept to less than 1.5 °C, two-thirds of the world’s coral reefs could be spared from serious degradation this century. With 2 °C or more of warming, reefs covered with living corals may become a thing of the past.

If you live in a small island nation in the tropics with historically low greenhouse gas emissions, there is a colonial air to the 2 °C limit. The rich countries are controlling your fate – through climate policy – and not even listening to your input.

Canada may look hypocritical in backing a 1.5 °C limit but not promising greater reductions in greenhouse gas emissions. However, the move has the potential to be more than mere tokenism and false hope.

Including the lower limit in the climate deal is a way of officially recognizing the harm likely to come to these more vulnerable countries. It will help ensure that these countries receive the needed international assistance, including terms of financing, investment in adaptation, and migration programs, which they have been promised through the UN system but has been slow to materialize.