The State of the Climate 2022 - Highlighted Article

From: The Global Warming Policy Foundation (GWPF)

By: Ole Humlum

Date: April 2023

The State of the Climate 2022

General summary

This report has its focus on observations, and not on output from numerical models, with a few exceptions (e.g. Figure 38). References and data sources are listed at the end of the report.

Air temperatures

Average air temperatures measured near the planet’s surface (surface air temperatures), or rather their deviation from the average calculated for a chosen reference period, are central to many climate deliberations. However, the significance of any short-term warming or cooling recorded in these datasets should not be overstated. Firstly, focusing on averages tends to hide the fact that we all deal with much larger temperature variations on a daily basis. Secondly, whenever Earth experiences warm El Niño or cold La Niña episodes, major heat exchanges take place between the Pacific Ocean and the atmosphere above, eventually showing up as a signal in the global air temperature. However, these do not reflect similar changes in the total heat content of the atmosphere-ocean system. In fact, the global net changes involved may be small; such heat exchanges may chiefly reflect redistribution of energy between ocean and atmosphere. Evaluating the dynamics of ocean temperatures is therefore equally as important as evaluating changes in surface air temperatures.

Relative to the whole period since 1850/1880, 2022 was warm, but cooler than most years since 2016. A moderate La Niña episode played out during the year, underlining the importance of ocean-atmosphere exchanges.

Many Arctic regions experienced record high air temperatures in 2016, but since then, including in 2022, conditions generally have turned somewhat cooler. The Arctic temperature peak in 2016 may have been affected by ocean heat, released from the Pacific Ocean during the strong 2015–16 El Niño and subsequently transported towards the Arctic. This underscores how Arctic air temperatures may be affected, not only by variations in local conditions, but also by variations playing out in geographically remote regions.

Many diagrams in this report focus on the time from 1979 onwards, reflecting the start of the satellite era, and the advent of a wide range of observations with nearly global coverage, including temperature. These data give a detailed view of temperature changes over time at different altitudes in the atmosphere. Among other phenomena, they reveal that a Stratospheric temperature plateau has prevailed since 1995.

Since 1979, temperatures in the lower Troposphere have increased over both land and oceans, but most clearly over land. The most straightforward explanation for this observation is that much of the warming is caused by solar insolation, but there may well be several supplementary reasons, such as differences in heat capacity and changes in cloud cover and land use.

Oceans

The Argo program has now achieved 19 years of global coverage, growing from a relatively sparse array of 1000 profiling floats in 2004, to more than 3900 in December 2021. Since their inception, these have provided a unique ocean temperature dataset for depths down to 1900 m. The data is currently updated to August 2020. Although the oceans are much deeper than 1900 m, and the dataset is still relatively short, interesting features are now emerging from these observations. (continue reading)

The State of the Climate 2022