Altimetry-based coastal sea-level time series (m) from January 1993 to June 2022 for the western Pacific and eastern Indian Ocean. The map (top) shows annual mean sea-level trend and location of regions summarized in the plots at the bottom left and right, and the transition from green to yellow colour corresponds to the 3.4 mm per year overall trend in the global mean sea-level rise. The plots (bottom left and right) show mean sea-level anomalies (blue) and estimated trend (orange line) for the South-East Asia and southern Oceania regions, respectively. Source: Copernicus Climate Change Service (C3S) – https://climate.copernicus.eu/sea-level, and Laboratory of Space Geophysical and Oceanographic Studies (LEGOS), France. Graphic: WMO
Altimetry-based coastal sea-level time series (m) from January 1993 to June 2022 for the western Pacific and eastern Indian Ocean. The map (top) shows annual mean sea-level trend and location of regions summarized in the plots at the bottom left and right, and the transition from green to yellow colour corresponds to the 3.4 mm per year overall trend in the global mean sea-level rise. The plots (bottom left and right) show mean sea-level anomalies (blue) and estimated trend (orange line) for the South-East Asia and southern Oceania regions, respectively. Source: Copernicus Climate Change Service (C3S) – https://climate.copernicus.eu/sea-level, and Laboratory of Space Geophysical and Oceanographic Studies (LEGOS), France. Graphic: WMO

By Gabrielle Tétrault-Farber
17 August 2023

GENEVA (Reuters) – Sea levels in the South-West Pacific are rising faster than the global average, threatening low-lying islands while heat damages marine ecosystems, the U.N. meteorological agency said on Friday.

In its State of the Climate in the South-West Pacific 2022 report, the World Meteorological Organization (WMO) said water levels were rising about 4 mm per year in some areas, slightly above the global mean rate.

That means low-lying territory such as Tuvalu and the Solomon Islands over time could become flooded, destroying agricultural and habitable lands with inhabitants unable to move to higher elevations.

The report added that marine heatwaves had occurred in a large area northeast of Australia and south of Papua New Guinea over more than six months, affecting marine life and the livelihoods of local communities.

(a) Linear trends in sea surface temperature (SST) (°C per decade) over the period 1982–2022. (b) Area-averaged time series of SST anomalies (°C) relative to the 1982–2022 reference period for the areas indicated in grey dashed lines in 5(a). Source: Derived from the Copernicus Marine Service remote sensing products available at https://doi.org/10.48670/moi-00168 (for 1982–2021) and https://doi.org/10.48670/moi-00165 (for 2022). Graphic: WMO
(a) Linear trends in sea surface temperature (SST) (°C per decade) over the period 1982–2022. (b) Area-averaged time series of SST anomalies (°C) relative to the 1982–2022 reference period for the areas indicated in grey dashed lines in 5(a). Source: Derived from the Copernicus Marine Service remote sensing products available at https://doi.org/10.48670/moi-00168 (for 1982–2021) and https://doi.org/10.48670/moi-00165 (for 2022). Graphic: WMO

WMO Secretary-General Petteri Taalas said that El Niño, a warming of water surface temperatures in the eastern and central Pacific Ocean that returned this year, would strongly affect the region.

“This will have a big impact on the South-West Pacific region as it is frequently associated with higher temperatures, disruptive weather patterns and more marine heatwaves and coral bleaching,” Taalas said in a statement.

The region last year recorded 35 natural hazards, including floods and storms, that killed more than 700 people, according to the report. These hazards directly affected more than 8 million people.

Although the number of reported disaster weather events in the region decreased last year compared to 2021, the scale of economic losses due to flooding and weather events increased, according to the report.

Flood damage, including in Australia and the Philippines, amounted to $8.5 billion, almost triple the previous year.

Pacific island sea levels rising faster than global average, WMO says

Maximum categories of marine heatwaves in the Pacific Ocean, and (b) the maximum duration over the year 2022 Source: Mercator Ocean international, France; derived from the Copernicus Marine Service remote sensing products available at https://doi.org/10.48670/moi-00168 (for 1982–2021) and https://doi.org/10.48670/moi-00165 (for 2022). Graphic: WMO
Maximum categories of marine heatwaves in the Pacific Ocean, and (b) the maximum duration over the year 2022 Source: Mercator Ocean international, France; derived from the Copernicus Marine Service remote sensing products available at https://doi.org/10.48670/moi-00168 (for 1982–2021) and https://doi.org/10.48670/moi-00165 (for 2022). Graphic: WMO

Climate change impacts increase in South-West Pacific

FIJI, 18 August 2023 (WMO) – Weather-related disasters and climate change impacts are unravelling the fabric of society in the South-West Pacific. Sea level rise threatens the future of low-lying islands whilst increasing ocean heat and acidification harms vital and vulnerable marine ecosystems, according to a new report from the World Meteorological Organization (WMO).

The State of the Climate in the South-West Pacific 2022 report provides a snapshot of climate indicators including temperatures, sea level rise, ocean heat and acidification, and extreme weather events in 2022. It also highlights the socio-economic risks and impacts on key sectors like agriculture. 

The report, along with an interactive story map, is one of a series of five regional reports and a global report from WMO providing the latest climate insights to inform decision-making.

The three-year-long La Niña event had a clear influence on temperatures in 2022. But despite its temporary cooling influence, it was still a warm year for the region. The mean temperature in 2022 was 0.2 °C to 0.3 °C higher than during the last strong La Niña event in 2011.

“The El Niño, which followed three years of La Niña conditions, is very likely to continue during the rest of the year. This will have a big impact on the South-West Pacific region as it is frequently associated with higher temperatures, disruptive weather patterns and more marine heatwaves and coral bleaching,” said WMO Secretary-General Prof. Petteri Taalas.

(a) Linear trends in ocean heat content (OHC) (in W/m2) in the Pacific Ocean over the period 1993–2022, integrated from the surface down to 700 m depth. Ocean warming rates in areas with water shallower than 300 m have been masked in grey owing to product limitations. (b) Area-averaged time series of upper 700 m OHC anomalies (joules per square meter (J/m2)) for the four areas indicated in grey dashed lines in 6(a). For each area, the linear trend over the full period is provided. Since the unit W has a dimension of J divided by time, the trend (changes with time) in ocean heat content per unit surface (J/m2) is shown in the unit W/m2. Source: Derived from the in situ-based Copernicus Marine Service product available at https://doi.org/10.48670/moi-00052. Graphic: WMO
(a) Linear trends in ocean heat content (OHC) (in W/m2) in the Pacific Ocean over the period 1993–2022, integrated from the surface down to 700 m depth. Ocean warming rates in areas with water shallower than 300 m have been masked in grey owing to product limitations. (b) Area-averaged time series of upper 700 m OHC anomalies (joules per square meter (J/m2)) for the four areas indicated in grey dashed lines in 6(a). For each area, the linear trend over the full period is provided. Since the unit W has a dimension of J divided by time, the trend (changes with time) in ocean heat content per unit surface (J/m2) is shown in the unit W/m2. Source: Derived from the in situ-based Copernicus Marine Service product available at https://doi.org/10.48670/moi-00052. Graphic: WMO

Compared to 2021, the number of reported disaster events decreased; however, economic losses increased. Economic damage due to flooding was US$ 8.5 billion, almost triple compared to the previous year, with most of the damage attributable to a series of flooding events in Australia. Tropical Storms Megi and Nalgae caused devastating flooding in the Philippines.

“Early warning is one of the most effective ways of reducing damage from disasters, as it empowers people to make risk-informed decisions for food security, as well as other sectors,” said Prof. Taalas.

“Despite continuous efforts to strengthen multi-hazard early warning systems, the present report clearly shows that there are still significant gaps to be addressed,” he said.

“The Early Warnings for All initiative … is critical in the Pacific, which is characterized by distinct disaster risk hotspots that are intensifying and expanding as climate-related hydrometeorological disasters intensify,” said Armida Salsiah Alisjahbana, Under-Secretary-General of the United Nations and Executive Secretary of the Economic and Social Commission for Asia Pacific.

“ESCAP and WMO, working in partnership, will continue to invest in raising climate ambition and accelerating the implementation of policy actions, which includes bringing early warnings to all in the region so that no one is left behind as our climate change crisis continues to evolve,” she said.

The report shows how the agriculture sector is one of the most critical sectors affected by climate-related disasters, echoing the national adaptation plans of many countries in the South-West Pacific. Enhancing the resilience of food systems is therefore a high priority. [more]

Climate change impacts increase in South-West Pacific