bobblog

Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the patterned world.
Compiled Sunday 25 June 23

WE'VE DONE IT – we have exceeded the 1.5C Threshold in June

As a sequel to last week's look at sea temperatures, I'm this week looking at surface air temperatures. The Climate watchers at climate.coernicus.eu have data that now shows that early this month temperatures exceeded the 1.5C Threshold.

In December 2015, the nations of the world adopted the Paris Agreement, under which they would pursue efforts to limit the rise in the climatological average global temperature to 1.5⁰C above pre-industrial levels.

Early this month for a few days the global-mean temperature was more than 1.5⁰C higher than the pre-industrial temperature for the month. (it has briefly been over the 1.5 C threshold before a few times… notably in 2015 around the time of the Paris Agreement signing, and also in early 2016 during the last El Nino. This is the first time it has happened in June, and that's one of the hottest months of the year.

As the current El Niño continues to develop there is good reason to expect periods in the coming twelve months during which the global-mean air temperature again exceeds pre-industrial levels by more than 1.5⁰C. What's more, according to a recent WMO report mentioned, there is a 98% likelihood that at least one of the next five years will be the warmest on record.

It must be stressed that the 1.5C and 2C limits set in the Paris Agreement are thirty-year period (climate epoch) targets for the average temperature of the planet. Passing the long-term global limits at any one time of year or any one place may not be of particular significance.

TROPICS
During the past week BRET and CINDY formed in the North Atlantic. There is a good potential that a cyclone will form this week off the Mexico west coast.
The MJO, a burst of extra energy in the tropics, is weak and in the Indian Ocean

WEATHER ZONES
The South Pacific Convergence zone SPCZ
is expected to retreat to the northern end of the Coral Sea.
A left-over convergence zone may linger about and to southeast of Southern Cooks
The subtropical ridge of light winds is expected to advance as far north as 17S between Fiji and Aitutaki,
so the westerly winds get as far north as Niue until end of local Monday
(wait until Tuesday for good conditions in the harbour).

HIGHS and LOWS

H1 well east of NZ should move away and H2 stay over mainland Australia this week.

The allows lows in between tom create lots of wind and swell.

L1 has been blocked to NE of North Island for days, flooding Gisborne area with tropical rains.
It is now expected to rotate clockwise and travel SW towards Chathams and then move off to the Sea.
By Thursday at 45S it may drop to 960 hPa, allowing an intense west/SW low across NZ and Tasman Sea with swells up to 9m in Tasman Sea and over 4m between NZ and the tropics. Avoid.

Low L2 starts near Cook strait and is expected to swirl NE around L1 then off to the east along 35S bringing a burst of extra squalls and swell. Avoid.

Low L3 is expected to move into the South Tasman Sea on Thursday and then towards Cook Strait/Chathams over the weekend. It MIGHT be followed by a High into the Tasman Sea early the following week.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
If you would like more details about your voyage, then check metbob.com to see what I offer.
Or Facebook at /www.facebook.com/metbobnz/
Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe at bottom).
Weathergram archive (with translator) is at weathergram.blogspot.co.nz.
Contact is bob@metbob.com or txt 64 277762212
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>