Monthly Northern Hemisphere Land Temperature Anomaly
Temperatures have been rising fast in March 2023. The image below shows the Monthly Northern Hemisphere Land Temperature Anomaly up to March 2023, with two trends added. The blue trend, based on Jan.1850-Mar.2023 NOAA data, points at a 3°C rise in 2032. The magenta trend, based on Oct.2010-Mar.2023 NOAA data, better reflects variables such as El Niño and sunspots, and illustrates how they could trigger a rise of more than 5°C in 2026. Anomalies are versus 1901-2000 (not versus pre-industrial).
Reducing emissions is the right thing to do, even though it comes with loss of the aerosol masking effect, a loss that causes a rise in temperatures, as discussed in an earlier post. Yet, despite pledges by politicians, greenhouse gas concentrations in the atmosphere keep rising, as discussed earlier, such as in this post.
- Daily Record: CO₂ was 424.83 ppm on April 17, 2023;
- Weekly Record: Average CO₂ was 422.88 ppm for the week beginning April 9, 2023; and
- Monthly Record: CO₂ in March 2023 was 421 ppm.
![]() |
[ from earlier post ] |
![]() |
[ click on images to enlarge ] |
NOAA has issued an El Niño Watch, and the range of possibilities toward the end of the year includes a strong El Niño (4 in 10 chance of Niño-3.4 ≥ 1.5°C) to no El Niño (1 in 10 chance).
This year (2023), the sea surface temperature (60°S-60°N) has already been above 21°C for 27 days. Such temperatures are unprecedented in the NOAA record that goes back to 1981. The image below shows the difference between all those years. The black line (2023) is as much as 0.3°C hotter than the orange line (2022), and we’re only just entering the upcoming El Niño.
![]() |
[ from earlier post ] |
The above image illustrates the danger of two tipping points getting crossed, i.e. the Latent Heat Tipping Point and the Seafloor Methane Tipping Point.
![]() |
Latent heat loss, feedback #14 on the Feedbacks page |
![]() |
[ see the Extinction page ] |
A huge temperature rise thus threatens to unfold over the next few years, as illustrated by the image on the right. Altogether, the rise from pre-industrial to 2026 could be more than 18.44°C by 2026.
This situation calls for urgent action. Reducing emissions alone won’t be enough. Carbon also needs to be removed from the atmosphere and oceans, through re-/afforestation, through pyrolysis of biowaste with the resulting biochar (and nutrients) returned to the soil and further methods. Even with a rapid transition to clean, renewable energy, with changes to food, land use, construction and waste management, and with removal of large amounts of carbon from the atmosphere and oceans, still more action is needed.
Accordingly, everyone is encouraged to support and share this Climate Emergency Declaration.
![]() |
[ image from Climate Emergency Declaration ] |
Links
• NOAA – Monthly Northern Hemisphere Land Temperature Anomaly
https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series/nhem/land/all/3/1850-2023
• NOAA – Recent Daily Average Mauna Loa CO2
https://gml.noaa.gov/ccgg/trends/weekly.html
• Climate Reanalyzer – Daily sea surface temperatures
https://climatereanalyzer.org/clim/sst_daily
• Sea surface temperature at record high
https://arctic-news.blogspot.com/2023/03/sea-surface-temperature-at-record-high.html
• IPCC keeps downplaying the danger even as reality strikes
https://arctic-news.blogspot.com/2023/04/ipcc-keeps-downplaying-the-danger-even-as-reality-strikes.html
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202303/supplemental/page-4
• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html