March 2025 near warmest on record, early heat in India and Pakistan, airborne phased array radar program canceled

There have been a few important news items in the weather world in the last 24 hours that I want to share with Balanced Weather readership.

March 2025 Ties for Warmest March on Record

The team at Berkeley Earth released their March 2025 temperature report, which showed that globally March 2025 equaled the warmest March on record, tying 2024 and 2016. Global temperature calculations are performed by different groups and often arrive at slightly different estimates. Copernicus, an affiliate of the European Center for Medium Range Weather Forecasting (ECMWF), found March 2025 to be second warmest just behind last year; its report indicated that Europe had their warmest March on record. NOAA estimated March 2025 as third warmest, just behind 2024 and 2016.

Regardless of the exact value, it is clear that the global air temperature continue its run of near record levels which has now been ongoing since 2023. What is particularly amazing about this is, as I discussed in a post a couple of days ago, we are just completing a winter that was characterized by a weak La Nina. Generally speaking, record global warmth in the past has been associated with El Nino as warmer ocean temperatures also contributes to warmer atmospheric temperatures. As Berkeley Earth stated in their report:

We had been expecting that the cycle of short-term warming that brought records in 2023 and 2024 would likely have peaked following the dissipation of El Niño last year, and that some temporary relative cooling would follow in 2025. However, temperatures during the first three months have remained quite warm…a possibility remains that 2025 could be as warm or warmer than 2024.

Berkeley Earth is now estimating a 34% chance that 2025 will surpass 2024 to end as the warmest year on record, and that it is nearly certain that 2025 will finish as one of the three warmest years on record along with 2024 and 2023.

Berkeley Earth, Copernicus and NOAA all concurred that the maximum Arctic sea ice extent reached in late March was the lowest on record, which dates back to 1979.

India, Pakistan Endure Early Heat

Sticking with the theme of warm global temperatures, I wanted to highlight this excellent article from CNN about the current intense early heat wave affecting India and Pakistan. I talked a little bit in a post last week about how late April into June is typically the hottest part of the year in this region, but that in recent years heat waves have been arriving earlier and that early heat was expected again this year.

As the CNN article discussed, Delhi has already reached or surpassed 40C (104F) three times this month, a level which is about 5C above normal. Southwest parts of Pakistan are forecast to reach 49C (120F) over the next few days, posing serious societal risks. From the article:

Ayoub Khosa, who lives in Balochistan’s Dera Murad Jamali city, said the heatwave had arrived with an “intensity that caught many off guard,” creating severe challenges for its residents. “One of the major issues is the persistent power outages,” said Khosa, who told CNN they could last for up to 16 hours a day. “This has intensified the impact of the heat, making it harder for people to cope,” he said.

The CNN article also gives a good overview of some of the impacts in the region expected in the coming decades as global temperatures continue to warm, including the real possibility that temperatures could literally “cross survivability limits.” It is a sobering but important read about the societal threats climate change is bringing to other parts of our planet.

NSF Airborne Phased Array Radar Project Cancelled

As shared by Dr. Robin Tanamachi on BlueSky yesterday, the director of the National Center for Atmospheric Research (NCAR) in Boulder notified staff and affiliates yesterday that the National Science Foundation’s (NSF) Airborne Phased Array Radar (APAR) project at NCAR was being terminated. NSF had announced the $91.8M APAR grant to NCAR in the summer of 2023, and the project was underway as part of NCAR’s Earth Observing Laboratory (EOL). It is unclear how much of the funding had already been allocated or utilized.

APAR should not be confused with the Phased Array Radar (PAR) program at the NOAA National Severe Storms Laboratory. The NSSL program is focused on research and development to explore the utility of PAR as part of the next generation weather radar network that will replace the currently aging WSR-88D, or NEXRAD, national federal Doppler weather radar network. In contrast to the current NEXRAD (and most weather radars) which feature a rotating radar dish to sample the atmosphere, phased array radars use a panel of fixed antenna elements which can be electronically controlled and steered to focus on specific areas of interest in the atmosphere. This allows for quicker, more targeted and more effective surveillance than the current rotating dish radar technology.

The goal of NCAR’s APAR project was the development of a phased array radar system to replace NCAR’s Electra Doppler Radar (ELDORA). ELDORA was the NCAR airborne radar system that was developed in collaboration with France’s Centre de Recherches en Physique de L’Environnement Terrestre et Planetaire (CRPE) in the early 1990s. ELDORA was flown in numerous field research programs over its three decades in service, including severe weather research projects such as VORTEX, tropical rainfall and cyclone research programs, and winter weather research projects.

Airborne weather radars play critical roles in projects such as these because they enable researchers to obtain targeted observations of storm structure and wind fields that would otherwise be impossible to capture. Research over the years with airborne weather radar led to NOAA having Tail Doppler Radars (TDRs) on its Hurricane Hunter aircraft, and eventually to the capability for this radar data to be assimilated into NOAA’s operational hurricane models. Studies have shown significant improvements to hurricane track and intensity forecasts due to the inclusion of aircraft reconnaissance data including TDR data.

While NSF was the primary funder of APAR, NOAA had provided about $10M for NCAR to develop the technology with the idea that APAR could eventually be utilized on new NOAA Hurricane Hunter aircraft that are scheduled for deployment in 2030. In his message yesterday, NCAR Director Dr. Everette Joseph said that the NSF cancellation was not believed to be related to concerns about the science of APAR or the ongoing work, and that NCAR remained strongly committed to APAR as a research technology. However, the cancellation of the NSF grant is obviously a major setback, and where it leaves the viability of APAR as either a replacement for the ELDORA system or for eventual use on NOAA reconnaissance aircraft is unclear.