Pumping up the weather

THE year 2022 effectively tied for Earth’s fifth warmest year since 1880 - and the last nine consecutive years have been the warmest nine on record, according to the latest analysis released by NASA.

Scientists from the Goddard Institute for Space Studies (GISS), NASA’s leading centre for climate modelling in New York have reported global temperatures in 2022 were 0.89 degrees Centigrade (C) above the average for NASA’s baseline period (1951-1980), continuing the planet’s long-term warming trend. Earth is now about 1.11 degrees C warmer than the late 19th century average.

“This is alarming,” admits NASA Administrator Bill Nelson, a former Space Shuttle astronaut. “Our warming climate is already making a mark. Forest fires are intensifying, hurricanes are getting stronger, droughts are wreaking havoc and sea levels are rising.”

He says NASA is deepening its commitment to addressing climate change and adds: “Our Earth System Observatory will provide state-of-the-art data to support our climate modelling, analysis and predictions to help humanity confront our planet’s changing climate.”

“The reason for the warming trend is that human activities continue to pump enormous amounts of greenhouse gases into the atmosphere, and the long-term planetary impacts will also continue,” explains Gavin Schmidt, director of GISS.

NASA scientists, working with leading international climatologists, have determined carbon dioxide emissions were the highest on record in 2022, despite a short-lived dip in 2020 due to the Covid-19 pandemic. Levels of these human-driven greenhouse gas emissions have rebounded since.

Using the Earth Surface Mineral Dust Source Investigation instrument that launched to the International Space Station last year, they have also identified some super-emitters of methane – another powerful greenhouse gas.

Earth’s Arctic region continues to experience the strongest warming trends – close to four times the global average – according to GISS research presented at the 2022 annual meeting of the American Geophysical Union, as well as in a separate study.

Communities around the world are already experiencing the impacts that scientists see as connected to the warming atmosphere and ocean – intensified rainfall and tropical storms, severe droughts and increased storm surges.

Among many other climate-driven weather events around the world – including the UK’s hottest ever daytime temperatures which peaked at 40.3 C in Coningsby, Lincolnshire – last year brought torrential monsoon rains that devastated Pakistan and a persistent megadrought in the US Southwest. In September, Hurricane Ian became one of the strongest and costliest hurricanes to strike the continental US.

NASA’s global temperature analysis is drawn from data collected by weather stations and Antarctic research stations, as well as instruments mounted on ships and ocean buoys.

Scientists analyse these measurements to account for uncertainties in the data and to maintain consistent methods for calculating global average surface temperature differences for every year. These ground-based measurements of surface temperature are consistent with satellite data collected since 2002 by the Atmospheric Infrared Sounder on NASA’s Aqua satellite and with other estimates.

NASA uses the period from 1951-1980 as a baseline to understand how global temperatures change over time. That baseline includes climate patterns such as La Niña and El Niño, as well as unusually hot or cold years due to other factors, ensuring it encompasses natural variations in Earth’s temperature.

Many factors can affect the average temperature in any given year. For example, 2022 was one of the warmest on record despite a third consecutive year of La Niña conditions in the tropical Pacific Ocean.

NASA scientists estimate that La Niña’s cooling influence may have lowered global temperatures slightly (about 0.06 degrees C) from what the average would have been under more typical ocean conditions.

A separate, independent analysis by the National Oceanic and Atmospheric Administration (NOAA) concluded that the global surface temperature for 2022 was the sixth highest since 1880.

NOAA scientists use much of the same raw temperature data in their analysis and have a different baseline period (1901-2000) and methodology. Although rankings for specific years can differ slightly between the records, they are in broad agreement and both reflect ongoing long-term warming.

NASA’s full dataset of global surface temperatures through 2022, as well as details with code of how NASA scientists conducted the analysis, are publicly available from GISS. 

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This article by Clive Simpson was first published by Central Bylines under the title 'Heating Earth drives more extreme weather'.

Taking our planet's pulse

Photo: Clive Simpson

High resolution radar data maps of Europe, North America and other key parts of the world captured on a space shuttle mission 14 years ago have been made public for the first time this month.

Former Nasa astronaut Kathy Sullivan, now head of the US National Oceanic and Atmospheric Administration (NOAA), welcomed the release of previously secret data. "The declassification of 30 metre elevation data represents a vast improvement over the previous freely available data set which resolved to just 90 m," she says.

This second tranche of high resolution data to be released under the direction of  President Obama follows on from highly accurate terrain maps of Africa which became available in October.   

Nasa's ground-breaking Shuttle Radar Topographic Mission (SRTM) recorded digital elevation data (DEMs) in February 2000 for over 80 per cent of the globe - but until now only a 90 m resolution version was released.

The 30 m resolution data was kept secret for use by the US military and intelligence agencies - but even the 90 m resolution data revealed for the first time detailed swaths of the planet's topography previously obscured by persistent cloudiness.

"SRTM was among the most significant science missions the shuttle ever performed," says Michael Kobrick, SRTM mission project scientist at the Jet Propulsion Laboratory (JPL). "It's probably the most significant mapping mission of any single type ever."

SRTM consisted of a specially modified radar system comprising two radar antennas - one located in the shuttle's payload bay, the other on the end of a 60 m mast extending into space.

The surface of Earth was mapped numerous times from different perspectives and the combined radar data processed at JPL in California to produce a series of global topographic maps.

Topography influences many natural processes, such as the distribution of plant communities and the associated animals that depend upon them, weather and rainfall patterns, and the flow and storage of surface water.

The digital elevation maps benefit many activities, from aviation safety to civil engineering projects, and the data is helpful in predicting and responding to flooding from severe storms and the threats of coastal inundation associated with storm surges, tsunamis and rising sea-levels.

Dr Sullivan says aid organisations, development banks and decision-makers in developing countries will be able to better map and plan for climate-driven challenges.

“Space-based observations are the foundation for applications so environmental intelligence services are increasingly vital to decision makers in all sectors of society as they confront a rapidly changing world and uncertain future.”

She called upon the world space community to develop new and more resilient Earth observation systems that are now increasingly relied upon “take the pulse” of our planet .

"Measured data of our planet tells us we are living in a worrying world," she said. "We are seeing longer, more frequent and hotter heatwaves over most land masses and we expect to see that trend continue in the future."

Andes mountains in Ecuador, home to the highest active volcano in the world

Data is also revealing the remarkable pace at which Arctic sea ice is continuing to shrink and thin, and the Northern Hemisphere's snow cover is decreasing as global mean surface temperature rises. 

“Sea level has risen an average of 3 mm a year in the last several decades and will continue to rise in the decades ahead which will exacerbate the hazards that coastal communities face from coastal storms,” said Dr Sullivan. “This is a problem because humankind is concentrating increasingly in the coastal settlements.

"Many aspects of climate change will persist for centuries, even if right now we cease all CO2 emissions forever. Carbon that has been emitted in the past decades is locked in and the process that it has unleashed will take centuries more to play out.

"All of this leads to heightened social vulnerability, in a world where the population will increase from the current seven billion to nine billion by 2040 - and that implies that we will have to double the current food supply globally if we are to feed that larger population," she added.

"We are moving into a very different world. Environmental intelligence is a really critical asset and product that the world needs from space. It provides us with foresight about conditions that have not yet come to exist and about the solutions we need to plan ahead for."