bdgwx

Berkeley Earth is now saying there is an 81% chance that 2023 will be the warmest in their dataset. https://berkeleyearth.org/june-2023-temperature-update/

Yes for GISTEMP on the 1951-1980 baseline. With more data that has been refined to 1.09 ± 0.06 C. Sent from my Pixel 5a using Tapatalk

Exactly. It's like how we use CDAS to track ENSO. It's not the best metric. But it's close enough to give us a pretty good idea of what ERSST is going to show. And since CDAS is near real-time it is still incredibly useful.

I was actually getting ready to respond to your question from this morning. I don't use CFSR for my own modeling because it's skill is subpar. Of the reanalysis datasets I generally use ERA5 and/or JRA55. That doesn't mean CFSR should be dismissed though. It's correlation with ERA and JRA is still very high. I use ERA5 a lot. In fact, it is one of my go-to sources for getting an early lead on what GISTEMP is going to report since it correlates at R^2 = 0.89. Note that Copernicus confirmed the new record via ERA5. And it's likely July 4th eclipsed that as well. ERA5 has a 2 day lag so we don't know for sure yet.

Nick Stokes just processed the June GHCN-M and ERSST files. I estimate the GISTEMP value for June at 1.09 ± 0.06 C.

There is a lot of a information coming out today. Sorry for the rapid posting. Anyway, the April CERES Earth Energy Imbalance came in at +1.81 W/m2. I realize the CERES EEI calculations have high uncertainty, but if the EEI truly is this high then there is more than enough warming in the pipeline to go well beyond 1.5 C.

Copernicus won't publish the official numbers from ERA5 for another couple days. However, based on Hausfather's twitter post we might expect GISTEMP to publish around 1.10 C for June. ERA5 correlates with GISTEMP at R^2 = 0.89. Note that the previous record was 0.92 C in 2022. It is all but guaranteed at this point that June 2023 will be a new record in the GISTEMP dataset as well.

For the first time in recorded history the global average temperature breached 17 C; at least according to CFSR anyway.

I was actually getting ready to post the GFS forecast as well. You scooped me. Anyway, yeah, July is already forecasted to start off quite warm. I noticed that there was a small blip down in the global SST last week. I wonder if that means excess heat is transferring from the ocean into the atmosphere now. As of this moment my June expectation is a tick up to 1.08 ± 0.10. Once the June data starts rolling in I can get that uncertainty envelop down to ± 0.06 prior to the GISTEMP update. By all indications June 2023 is going to be the warmest June on record.

BTW...the page is buried pretty well. But you can get the probability density function corrected forecast (bias corrected) for the CFS from the following link. It took me forever to find it a couple of weeks ago and Google isn't much help. https://www.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/CFSv2SST8210.html

And the bias corrected CFS forecast is even lower at maybe +1.4.

I cannot disagree. If I have understood the Brown & Caldeira method correctly they only make predictions based on the current state of the climate system. In other words they do not take into account the expectation of future ENSO (or other highly correlated climatic element) states. This may explain why I get higher odds of a new record. My model is simpler (more like a multiple regression that minimizes RMSE), but incorporates the future expectation of ENSO and to a lesser extent total solar irradiance (which I do find to be at least minimally correlated with global temperatures). Both of which can be predicted 6 months in advance with reasonable skill. And yes, your point about global SST is well taken. My expectation is that the atmosphere will catch up to the higher SSTs in the next couple of months. It may be interesting to note that my model does not use SST has an input right now. In that regard one might argue that even I may be underestimating the warming potential in the later half of the year, but I'm going to remain more guarded on that matter as I also think a reversion to the trend may also be on the horizon. Afterall highly deviant increases/decreases tend to reverse some eventually. BTW...my current June expectation for GISTEMP is 1.07 ± 0.10 C. To put that into perspective even taking the ~2.5% chance that it comes in -0.10 C below the expectation at 0.97 C it will still easily surpass the previous record of 0.92 C set all the back in 2022. That should raise some eyebrows.

Brown & Caldeira are now saying there is a 57% chance of new GISTEMP record.

Berkeley Earth says there is a 54% chance of new record in their dataset.

@GaWx I bet you're right. I've not been able to find any daily ERSST updates. And I can't disagree, I see a very high correlation between NCEP/NCAR vs ERSST in ENSO 3.4 region at R^2 = 0.98. So while they don't match exactly it is very close. I certainly wouldn't dismiss it.

Someone can correct me if I'm wrong but it is my understanding that CDAS, which stands for Climate Data Assimilation System, is actually the model core for the NCEP/NCAR reanalysis. Or at least that is what the NCEP/NCAR built upon. The NCEP/NCAR reanalysis is known to be subpar. But I don't think that is justification for dismissing it outright. I do wonder if it wouldn't be better for Levi Cowan to use a more accepted product like OISST or ERSST though.

Several months back I suggested that if the shenanigans kept up in the Antarctic then perhaps it might be time for a dedicated thread. The data collected by the IPCC suggested that sea ice extents may increase through 2030 at the very least. Yet here we are with record lows. Perhaps the time for a dedicated thread as come.

Here is my latest expectation for GISTEMP which includes the June IRI ENSO ensemble forecast. Jan: 0.87 ± 0.01 C (3m lagged ENSO -0.99) Feb: 0.98 ± 0.01 C (3m lagged ENSO -0.90) Mar: 1.21 ± 0.01 C (3m lagged ENSO -0.86) Apr: 1.00 ± 0.01 C (3m lagged ENSO -0.71) May: 0.94 ± 0.02 C (3m lagged ENSO -0.46) Jun: 1.05 ± 0.12 C (3m lagged ENSO -0.11) Jul: 1.03 ± 0.22 C (3m lagged ENSO +0.13) Aug: 1.06 ± 0.23 C (3m lagged ENSO +0.39) Sep: 1.10 ± 0.24 C Oct: 1.13 ± 0.25 C Nov: 1.16 ± 0.26 C Dec: 1.17 ± 0.26 C 2023 Average: 1.06 ± 0.08 with 75% chance of a new record (>= 1.03)

The June IRI ensemble suite just got published. The statistical+dynamical average peak jumped up 0.2 to 1.5 on this update. https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table IRI June Seasons (2023 – 2024) Model JJA JAS ASO SON OND NDJ DJF JFM FMA Dynamical 1.295 1.539 1.679 1.761 1.746 1.598 1.473 1.264 1.009 Statistical 0.749 0.785 0.825 0.840 0.846 0.812 0.734 0.579 0.415 All 1.120 1.298 1.406 1.466 1.403 1.248 1.125 0.899 0.670

The bias corrected CFS peak has come down about 0.5 in the last few weeks.

This is great. I've been looking for an updated volcanic aerosol dataset for awhile now. I had no idea this existed. They even have it in an easy csv file format and it goes through 2022. Anyway, it looks like H2O adds about 0.1 W/m2 to the imbalance. Like you said the AOD portion is fading rapidly though so if the H2O portion is long term like scientists are expecting then we should expect a net positive, albeit small, effect from Hunga Tonga soon. Somewhat interesting...my machine learning model said a 5 month lag with GISTEMP for this volcanic aerosol dataset was optimal. My model was showing a -0.05 C adder to start the year and wanes to -0.02 C by the end after I extrapolate out the AOD decay based on what happened with Pinatubo.

ERA has a pretty high correlation with the traditional datasets. It correlates with GISTEMP at R^2 = 0.89. It's the same as JRA. The previous record via JRA was +0.34 (1991-2020 baseline) in 2019. So far the 2023 June value is +0.61. JRA correlation with GISTEMP is R^2 = 0.89 https://climatlas.com/temperature/jra55_temperature.php Similarly with the GFS as well. The previous record via GFS was +0.55 (1981-2010 baseline) in 2019. So far in 2023 June value is 0.68. GFS correlation with GISTEMP is R^2 = 0.78 http://www.karstenhaustein.com/climate.php

The May GISTEMP value came in at 0.94 C. This was a massive deviation and miss from my 1.05 ± 0.08 C expectation. A miss of that magnitude does not happen very often. And because May came in so much lower than my expectation my current June expectation drops to 1.06 ± 0.15 C. However, the Jan, Feb, and Mar values all came in 0.01 C higher so instead of dropping 0.11 from the yearly sum we only dropped 0.08 so the impact on the yearly average isn't as much as one might naively think. My current expectation for the full year average is now 1.05 ± 0.09 resulting in a probability of a new record (>= 1.03 C) of 67%. I should note that Nick Stokes' TempLS dataset has a very high correlation with GISTEMP (R^2 = 0.97) and gets released several days prior to GISTEMP. His dataset was suggesting the May anomaly would come in at 0.96 ± 0.06 C. As of the time of my 1.05 ± 0.08 C expectation I was not exploiting Nick's data. I will do so going forward.

Relevant...

I'm skeptical of the Hunga Tonga effect myself. I've been tracking stratospheric temperature anomalies since the eruption and while there were very noticeable effects for about 8 months I can no longer see much of an effect. That's not to say that I don't think it will cause some warming, but I think it will be low enough that it will be indistinguishable from the noise. I do think there is merit to the marine aerosol reduction though. Even a tenth of watt change in the Earth energy imbalance (EEI) would be significant. Many of the marine emission rules went into effect in 2020 so it quite possible that at least some of the record setting temperatures can be traced back to the high EEI. If you look at @chubbs post above you'll see the CERES EEI is now +1.5 W/m2. CERES EEI calculations are known to have high uncertainty [Loeb et al. 2021], but +1.5 W/m2 is still high enough to raise eyebrows. There's no doubt that the main contribution of the higher 2023 temperatures is GHGs though. I think what is catching some off guard (like myself) is that the temperatures are higher than our expectations given that the 4 month lagged ONI corresponding to May was -0.7...well into La Nina territory. In other words, we're still under the La Nina influence albeit transitioning out now. Is it transient variation or is the warming really accelerating? One other significant contributing factor to the North Atlantic SSTs are believed to be high due to very low Saharan dust levels.