“Rapidly Rising Temperatures: How Climate Normals are Shifting and What it Means for New Zealand”

New Zealand’s National Institute of Water and Atmospheric Research (Niwa) has recently updated its “climate normal” baseline to reflect the fact that the average temperature experienced by the country is now higher than it used to be. This shift in temperature has led to a decrease in the number of months with “below normal” temperatures, with last August being the first in 74 months to meet that colder threshold.

According to Niwa climate database scientist Raghav Srinivasan, human-driven warming is not the only factor causing year-to-year swings in seasonal rainfall and temperature. Natural drivers such as El Niño and La Niña also play a significant role in influencing climate patterns.

In a new study, Srinivasan and colleagues suggest the use of additional “alternative normals” that could be updated more frequently to better reflect the current climate conditions. This approach would help incorporate extreme events like Cyclone Gabrielle’s rainfall totals in a timelier manner, rather than waiting for the next 10-year update cycle.

The study also explored how climate change will impact New Zealand’s future wet and dry weather extremes. Even in regions with little change in annual average rainfall, a world 3°C warmer could bring 10% more rain on the wettest days and 10% less on the driest days. This information can serve as a valuable tool for planning for future weather events.

Scientists predict more extreme dry spells punctuated by increasingly intense rainfall events as global temperatures continue to rise. The analysis also highlights the challenges that regions in New Zealand will face, with wet regions becoming wetter and dry regions experiencing more intense drought periods.

Overall, the research underscores the need for proactive measures to address the impacts of climate change on New Zealand’s weather patterns. As temperatures continue to increase, it is crucial for policymakers and communities to prepare for the worst-case scenarios and adapt to the changing climate conditions.