New study says average temperatures are rising in Nova Scotia

Our planet is changing. So is our journalism. This story is part of a CBC News initiative entitled Our Changing Planet to show and explain the effects of climate change and what is being done about it.

Leaders from around the world are meeting at the United Nations Climate Change Conference in Glasgow this weekto discuss our changing climate and how to tackle the growing problem moving forward.

The Conference of Parties (COP), as it's known, meets every year and is the global decision-making body set up in the early 1990s to implement the United Nations Framework Convention on Climate Change and subsequent climate agreements.

• Have questions about COP26 or climate science, policy or politics? Email us: ask@cbc.ca. Your input helps inform our coverage.

The effects of climate change are being felt all over the planet, and Nova Scotia is no exception.

Anew study out of Nova Scotiaoffers even more evidence that temperatures in theprovince are on the rise, particularly over the past couple of decades.

The study, authored by biology professors David Garbary and Nicholas Hill from St. Francis Xavier University in Antigonish, looksat temperature records from 1961 to 2020 for 16 locations across the province.

The data shows averagetemperatures in Nova Scotia have risen dramatically since 1998 when compared to the 1961-1990 normals.

In Halifax, Western Head, Kejimkujik, Greenwood and Cheticamp, increases of more than 1 C were observed.

When breaking down the temperatures month by month, increases were more apparent in the autumn months where first frosts have been occurring later, the authors found.

On average, the 1998-2020 numbers showed an increased length of the frost-free period of 9.2 days, compared to the 1961-1990 period. The most dramatic jump was observed in Kejimkujik, where the frost-free period increased by 37 days.

Ocean temperature impacts

Nova Scotia is almost entirely surrounded by water, andas a result, ocean temperatures are an integral part of the province's changing climate.

Aseparate 2014 studyrecognized the Atlantic coast of Nova Scotiaas one of the ocean's warming hotspots.

Scientists agree thatgreenhouse gases are the ultimate cause for rising land and ocean temperatures around the world, but the new St. FXstudy also considersother impacts.

The authors found temperatures in Nova Scotia tended to be a bit cooler during El Nio events and warmer during La Nia events.Overall, however, the statistical significance during these phases was weak.

The study also references the Atlantic multidecadal oscillation, or AMO for short, which refers to changes in sea surface temperatures in the Atlantic ocean over long periods of time, roughly 60 to 80 years.

The AMO is currently in a warm phase that began in the late '90s.

Given temperatures have been rising in Nova Scotia since the '60s, the study saysthe positive AMO seems unlikely to explain the rise. However, the switch to a positive phase in the late '90s does "provide a partial explanation of gross temperature change."

With global temperatures expected to increase in the coming years, the study points out that it remains to be seen if future warming in Nova Scotia willbe moderated when the AMO enters a negative phase.

MORE TOP STORIES