Early warning system is an adaptive measure for climate change, using integrated communication systems to help communities prepare for hazardous climate-related events. A successful EWS saves lives and jobs, land and infrastructures and supports long-term sustainability. Early warning systems will assist public officials and administrators in their planning, saving money in the long run and protecting economies. The UN, working in diverse partnerships, has introduced a number of innovative early warning systems initiatives in vulnerable areas around the world.

UNDP’s Signature Programme, "Strengthening Climate Information and Early Warning Systems for Climate Resilient Development and adaptation to climate change" is a comprehensive programme operating across Africa, Asia and the Pacific. Systems in place at the sub-regional and regional levels ensure preparedness and rapid response to natural disasters, using a model that integrates the components of risk knowledge, monitoring and predicting, dissemination of information and response to warnings.

In Uganda, where 64 per cent of the population relies on agriculture for subsistence, most of the weather stations fell into disrepair following civil war, changes in government and poor maintenance. The Strengthening Climate Information and Early Warning Systems (SCIEWS) project has replaced outdated and inadequate meteorological stations with updated systems, improving disaster risk reduction with more effective means of generating and disseminating information.

In Southeast Asia, long coastlines and low-lying countries make the region particularly vulnerable to increasing extreme weather conditions. In Cambodia, for example, more than 1.7 million people in 2013 were affected by floods with a loss of $365 million; by 2016 the number of people affected by floods rose to more than 2.5 million people, indicative of an increase in climate-related flooding. A four-year program implemented by UNDP with the Government and other partners, entailed installing and re-activating existing Automatic Weather and Agrometeorological Stations and Automatic Hydrological Stations across the country. Farmers now can access climate bulletins for detailed and carry out substantial planning to avoid costly consequences, both in money and lives.

UNEP’s Climwarn project, a partnership with entities in Burkina Faso, Ghana and Kenya, has replaced rudimentary meteorological methods with a more sophisticated system using modern technology that alerts communities of potential floods and other risks. which is then communicated to rural regions through SMS and email, aiding them in better preservation of their crops and livelihoods.

UN entities also provide support as implementing partners for the Climate Risk and Early Warning Systems (CREWS) initiative, which was launched at the UN Climate Change Conference in Paris in 2015. CREWS boosts capacity of Multi-Hazard Early Warning Systems and is operating in 19 countries in Africa and the Pacific, including Least Developed Countries (LDCs) and Small Island Developing States (SIDS), most prone to tropical cyclones and floods. In June 2018, CREWS announced the programme would be rolled out in the Democratic Republic of Congo, Burkina Faso, Mali and Niger. CREWS Steering Committee continues to identify new countries in Africa and Asia where programs can be financed.