TCC Activity Report for 2021
In 2021, the Tokyo Climate Center (TCC) continued to support the climate services of National
Meteorological and Hydrological Services (NMHSs) in Asia-Pacific countries by providing andenhancing data and products, holding training seminars, publishing quarterly newsletters andparticipating in online international meetings.
1. Enhancement of data/products/tools on the TCC website
1.1 Issuance of special reports on extreme events
In a mandate role as a WMO Regional Climate Centre (RCC) in Regional Association II (RAII), TCC
monitors world climate conditions with focus on Asia and its surrounding area. The Center issues reports
on extreme climate events and summaries of the Asian summer/winter monsoon on its website(https://ds.data.jma.go.jp/tcc/tcc/products/clisys/reports/index.html).
A series of heavy snowfall events hit Japan from mid-December 2020 onward, especially on the Seaof Japan side, with new records observed in some places. TCC issued a press release on factors behind
this snowfall and low temperatures around the country, and uploaded an English-language report to its
website (https://ds.data.jma.go.jp/tcc/tcc/news/press_20210115.pdf).
Japan experienced record-warm weather conditions in March, and TCC issued a report summarizing
the related characteristics of atmospheric circulation anomalies and the underlying mechanisms. The
information
waspublishedinEnglishontheCenter’s
website(https://ds.data.jma.go.jp/tcc/tcc/news/press_20210421.pdf).
In mid-August 2021, areas from western to eastern Japan experienced record-heavy rain. In thiscontext, the Japan Meteorological Agency (JMA), with the help of the Tokyo Climate Center Advisory
Panel on Extreme Climatic Events (see TCC News No. 28), investigated atmospheric and oceanic
conditions considered to have contributed to such climate extremes and summarized related primaryfactors.
The
comprehensive
reportisavailable
onthewebsite(https://ds.data.jma.go.jp/tcc/tcc/news/press_20210924.pdf).
1.2 Upgrade of the Global Ensemble Prediction System for One-month Prediction
JMA upgraded its Global EPS for one-month prediction on 1st April 2021, increasing the number ofvertical model levels from 100 to 128 and improving surface/atmospheric initial conditions. Hindcast
gridded data and verification charts for the new EPS are available to registered users via the TCC website.
Elsewhere, the provision of 2.5-degree forecast and hindcast gridded data for one-month prediction
was terminated on 25 March 2021.
The ensemble size of forecast data for each initial day was changed from 24 to 25 for Tuesday andfrom 26 to 25 for Wednesday.
1.3 Release of Indian Ocean Dipole products

The Indian Ocean Dipole (IOD) is a major mode of interannual climate variability in the tropics,
significantly affecting climate conditions on regional and global scales. From discussions with NMHSs(such as those held during the 2019 visit to Meteorological Service Singapore), TCC recognized a needto gather information on this mode. In response, the Center released new online IOD products on 28
January 2021, including data related to monitoring and associated effects on global climate/atmosphericcirculation. A brief description of the products is provided in TCC News No. 63.
1.4 Update of website on RA II Information sharing for Climate Services

For the improvement of climate services and successful implementation of the Global Framework forClimate Services, it is important to share information on the services, good practices and lessons learnedin climate-related activities, especially among NMHSs in climatologically similar region. However,such important information has not so far been fully shared among NMHSs in WMO RA II. In response
to Decision 35 taken at the 16th session of Regional Association II (RA II) to improve information
sharing on climate services in the region, TCC operates a dedicated website(https://ds.data.jma.go.jp/tcc/RaiiInfoshare/, see TCC News No.36 for more information).
A November 2021 questionnaire survey conducted by TCC for updating of the website generated
responses from more than 10 Members thanks to the kind cooperation of their involvement. Based on
the information provided, the site was updated and refined in December 2021.
1.5 Operational application of new climatological normals for 1991 – 2020

Under the Technical Regulations of the World Meteorological Organization (WMO-No. 49),
climatological standard normals are averages of climatological data computed for 30-year periods (e.g.,
1 January 1981 to 31 December 2010, 1 January 1991 to 31 December 2020 and so forth.) Countries
should calculate climatological standard normals as soon as possible after the end of a standard normalperiod.
TCC switched from the previous climatological normal period of 1981 – 2010 to 1991 – 2020 on 19
May 2021. TCC products (other than those from WMC Tokyo for long-range forecasting and Model
Prediction for NINO Regions) have been based on this new period since that date.
2. Capacity development
TCC holds annual training seminars as part of capacity-development activities related to its role as anRCC in RA II. In addition to running annual training seminars, it also arranges expert visits to and hosts
visitors from NMHSs to support exchanges of views on climate services and the effective transfer oftechnology.
2.1 Training seminar
TCC holds training seminars every fiscal year (April – March), with the December 2021 event
covering one-month forecasts. The seminar was held online for the first time due to COVID-19. Detailsof the events are reported in TCC News No. 66.
3. International meetings
3.1 Regional Climate Outlook Forums
RCCs are expected to actively contribute to and lead profound discussions in Regional Climate
Outlook Forums (RCOFs). In 2021, TCC experts participated in the following RCOFs in Asia:- Seventeenth session of the Forum on Regional Climate Monitoring, Assessment and Prediction forRegional Association II (FOCRA II-17) held online, on 7 May- Nineteenth session of the South Asian Climate Outlook Forum (SASCOF-19) held online, from 26
to 28 April- Twentieth session of the South Asian Climate Outlook Forum (SASCOF-20) held online, from 27

to 30 September- Ninth session of the East Asia winter Climate Outlook Forum (EASCOF-9) held online, on 4November- Seventeenth session of the ASEAN Climate Outlook Forum (ASEANCOF-17) held online, from22 to 26 November- Twentieth session of the North Eurasian Climate Forum (NEACOF-20) held online, on 20 May
TCC attendees gave presentations on seasonal predictions based on JMA’s numerical model andparticipated in discussions toward the formulation of a consensus statement on regional forecasts.
In collaboration with TCC, a representative from the World Meteorological Centre Tokyo (WMCTokyo) attended FOCRA II-17, SASCOF-19, SASCOF-20, and NEACOF-20 online. WMC Tokyo also
produced presentation materials for ASEANCOF-17.

4. Publications
TCC has published its newsletter (TCC News) on a quarterly basis since 2005. The publication isintended to enhance communication and provide information to NMHSs and related communities about
recent TCC developments, events and activities as well as details of the Center’s reports on the state of
the climate, monitoring results and outlooks. In 2021, TCC News No. 63 – 66 were issued and madeavailable on the TCC website.
5. Plans for 2022
- Contribution to the Global Framework for Climate Services (GFCS)RCCs are expected to play a major role in the implementation of the GFCS. TCC plans to further
strengthen its activities and lead RA II’s contribution to the Framework. Such activities include theprovision of further assistance to NMHSs for better climate services, as well as maintenance of the portalsite for Information Sharing on Climate Services in RA II.
- New/upgraded data, products and tool development
As per TCC News No. 65, on 14 February 2022 JMA upgraded its Seasonal Ensemble Prediction
System (Seasonal EPS) from JMA/MRI-CPS2 to JMA/MRI-CPS3, which was adopted as the basis forthree-month prediction products such as gridded date files, forecast maps and verification maps. Model
forecasts of SST anomalies for NINO regions (provided via the El Niño and Indian Ocean Dipole onlineresources) were also influenced by the upgrade.
Specifications for operational forecasting were changed from 13 ensemble members every 5 days to5 ensemble members every day. The baseline period for seasonal forecast products was also changed to1991 – 2020.
In line with this upgrade, TCC plans to switch from CPS2 to CPS3 data provision as per thedescription page. CSP2 2.5-degree gridded data (GPV) for three-month and warm/cold-season
prediction were discontinued in January 2022, and those for six-month prediction will still be provided
for a few months in parallel with the new CPS3 gridded data.
Further enhancements of the new dataset planned for autumn 2022 include the utilization of JRA-3Q(Japanese Reanalysis for Three-Quarters of a Century), COBE-SST2 (Centennial in situ ObservationBased Estimates of the Variability of SST and Marine Meteorological Variables, version 2), andMOVE/MRI.COM-G3 (the Multivariate Ocean Variational Estimation/Meteorological ResearchInstitute Community Ocean Model - Global version 3). These improvements will influence several
products on the TCC website, including the interactive iTacs tool, with details to be provided in due
course.

- Capacity development
In the last quarter of the year, TCC will hold its annual training seminar with a dozen invited experts
as attendees. The Center will also continue to dispatch experts to NMHSs as necessary and host visitorsfrom NMHSs upon request. The format of these activities (i.e., online or in person) will depend on
COVID-19 developments.
(WAKAMATSU Shunya, Tokyo Climate Center)