Climate change is daunting, partly because of the huge numbers and insider jargon to confuse the average person.

So, as part of the Covering Climate Now series, this week the New Zealand Herald has created a daily quiz for you to test your knowledge and sort the facts from the fiction.

The questions are focused on the kinds of greenhouse gas emissions which some nations have agreed to reduce under international agreements to limit climate change.

Under these agreements and the upcoming Zero Carbon Bill, New Zealand has three emission reduction targets: 5 per cent below 1990 emissions by 2020, 30 per cent below 2005 levels by 2030 and 50 per cent below 1990 levels by 2050.

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The gases we need to reduce come from four sectors: which do you think are the most important in New Zealand?


New Zealand's greenhouse gas emissions are dominated by the agriculture and energy sectors. The agricultural sector is the biggest source of warming emissions, but more than half of New Zealand's emissions come from other sectors.

Emissions from international aviation and shipping are not included within these figures. The figures are produced for international agreements that only consider emissions that a specific nation is solely responsible for.

Emissions are also tracked for specific industries and activities. See if you can rank these four.


The three key sources of New Zealand energy sector emissions are: road transport 17.9 per cent, manufacturing and construction 8.6 per cent, and electricity generation 4.4 per cent.

The three key sources of agricultural emissions are: dairy cattle 22.5 per cent, sheep 12.7 per cent, and beef cattle 8.1 per cent.

How do New Zealand's greenhouse gas emissions compare globally?


New Zealand's per person emissions place it firmly with the high emissions group of developed countries. Countries like the United Kingdom have much lower per person emissions.

New Zealand's total emissions are a relatively small part of the world's total, but we have still made a commitment to reduce them.

Let's take a closer look at these figures. How do you think New Zealand's emissions for energy and transport compare globally?


Without agriculture, New Zealand's emissions are much closer to the United Kingdom's. From a global perspective, it is sobering that China's per-person energy emissions - from its almost 1.4 billion people - are basically the same as New Zealand's, and higher than the United Kingdom's.

How do New Zealand's agricultural emissions compare globally?


The importance of agriculture to New Zealand can be clearly seen in its per-person emissions from agriculture. New Zealand has the highest agricultural emissions per person in the OECD.

A large proportion of New Zealand's electricity generation is renewable - bringing agricultural emissions into focus. Some other countries have far more emissions from coal- and gas-fired power stations.

"As other countries transition to renewable power generation they will also face an agricultural emissions challenge" says Dr Harry Clark, Interim Climate Change Committee Member, "and those countries are watching to what New Zealand does."

All the emissions numbers reported here use the global warming potential method of estimating the warming contribution of different gases - based on the average warming for each gas over 100 years. This method is the metric New Zealand has agreed to use for the 2030 emissions reduction target.

In the next article we will look at the difference between agricultural and energy sector emissions.

Credits:
Data is from the Ministry for the Environment's Emissions Tracker and the OECD's reporting. All emissions were for 2017 except for China's which were from 2012.

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Design by Kat Greenbrook of Rogue Penguin

This article was supported by the Aotearoa New Zealand Science Journalism Fund.