Response: Are we doing enough? How much time do we have left?

Are we doing enough? How much time do we have left?

(Image: Monika Kubala)

Are we doing enough? How much time do we have left?

Summary

Under the 2015 Paris Agreement, cutting greenhouse gas emissions in half by 2030 might have given the world a 63% chance of staying below 2°C of global average temperature rise, and a 50% chance of staying below 1.5°C. This is the threshold associated with the most dangerous climate threats and what was agreed by most countries at the time. These risky odds do not include most feedback loops and non-linear (ie impossible to reverse) tipping points.

In spite of Covid-19 emissions reductions, the 2020 UN Gap Report paints a bleaker picture:

“The world is still heading for a catastrophic temperature rise in excess of 3°C this century – far beyond the Paris Agreement goals of limiting global warming to well below 2°C and pursuing 1.5°C.”UN Emissions Gap Report, 09 December 2020

“New Zealand’s Paris Agreement target is inconsistent with the Government’s goal of keeping the average temperature increase to within 1.5°C, officials have told ministers. The advice from the Ministry for the Environment was given to Climate Change Minister James Shaw in February and obtained by Stuff under the Official Information Act.

“Shaw was told the target allows some 85 million tonnes more emissions between 2021 and 2030 than would be compatible with a 1.5°C goal – putting the country over budget by about one year’s current emissions.” –  Stuff July 2020

We have run out of time to return our climate to the stability that our global civilization enjoyed for the past several thousand years. We must cut net emissions to limit the magnitude of impacts. The faster we can do this, the more we can save, and the less we will lose—for ourselves and our children’s futures.

Fig. 1: Projected temperature increases under current policies (Image: Nature)
Fig. 2: New Zealand’s commitments to reduce net emissions are insufficient to stay within what the IPCC deemed as ‘safe’ temperature increase of 1.5°C above pre-Industrial levels. We also exceed the ‘dangerous’ 2°C levels and instead are aiming for 3°C (Image: Nature)
Fig. 3: Sheep and cows together emit 36.5% of methane emissions. (Image: New Zealand Greenhouse Gas Inventory 1990-2018 [April 2020]).

“The idea of planting trees in vast areas to remove carbon dioxide from the air and reduce the impact of climate change, for example, has attracted a lot of attention, with some claiming it’s the best “low-hanging fruit” approach to pursue, McElwee said. But large-scale tree planting could conflict directly with food security because both compete for available land. It could also diminish biodiversity, if fast-growing exotic trees replace native habitat.” –  Rutgers University, 2020

Fig. 3: Under the existing Emissions Trading Scheme, the One Billion Trees project makes the financial incentives to plant exotic trees for forestry far greater than regenerating native forests. Radiata pine sequester carbon faster (while ignoring how much natives sequester in soils) but carbon savings in radiata is lost by the carbon-emitting harvesting methods, transporting felled timber (generally offshore), converting timber into wood products most of which will ultimately be burned or rot, releasing their carbon. Meanwhile, the biodiversity values and essential ecosystem services provided by natives are being sacrificed.

Explainer

Net emissions:

Net emissions means gross greenhouse gas emissions (‘spending’ carbon) from all industrial activities, burning fossil fuels for energy, and agriculture, minus carbon sinks (‘saving’ carbon) from forestry, changing agricultural to improve soils, and regenerating natural ecosystems. However, instead of declining, global emissions continue to increase each year. Due to reduced transport, Covid-19 meant a temporary respite of carbon dioxide emissions. However, that has not reduced agriculture emissions in New Zealand and elsewhere. Manufacturing in China has also resurged. Moreover, dangerous tipping points are being breached, which means natural carbon sinks are now becoming sources of methane and carbon dioxide.