The African Monsoon Multidisciplinary Analysis for 2050 (AMMA-2050) project: The University of Leeds helps advise on future climate change over West Africa.

The AMMA-2050 project; funded by Future Climate for Africa, aims to provide new meteorological and climate science that can improve decisions made by people in West Africa over the next 5–40 years. Using state-of-the-art high resolution models over West Africa, and internationally recognized datasets (such as the CMIP5 and CORDEXclimate datasets), the project aims to further global understanding of high impact rainfall over West Africa. AMMA-2050 is a consortium of partners in Europe and Africa led by Professor Chris Taylor of CEH Wallingford (who holds a Visiting Professor position at the University of Leeds).

High impact weather is a broad topic that covers all weather events that can have a detrimental effect on human life. Over West Africa, common examples include: incorrect prediction of the best time to plant crops (onset dates and false onsets), intense rain events (that can cause flooding or the spread of water-borne diseases), prolonged periods of little rainfall which kill crops or cause water shortages (agronomic dry-spells), heatwaves, high-velocity wind events, and lightning.

The AMMA-2050 project is a continuation of the very successful AMMA project (Redelsperger et al. 2009). AMMA-2050 involves 16 institutions from the UK, France, Senegal, Burkina Faso, Ghana, and the Ivory Coast. As well as furthering scientific understanding behind the causes of, and impacts of, climate change across West Africa, AMMA-2050 has other ambitious goals; such as:

• Capacity building (both academically and institutionally). AMMA-2050 is training the next wave of young scientists who will lead research on West Africa in the future. As part of this goal, early career researchers in AMMA-2050 regularly collaborate on projects independent of more senior scientists to build new personal and academic bonds. The project also aims to build individual nations’ capacity to adapt to climate change. This is done through knowledge exchange and building personal links between scientists and policymakers across West Africa.
• Empowerment of women (academically and institutionally). AMMA-2050 is committed to increasing the number of women producing world leading research on the West African climate. In addition, when considering the way that climate advice is disseminated to local forecast users, scientists in AMMA-2050 strive to make sure the most marginalized and vulnerable people in society have equal access to much needed information.
• Decision first science. Often, science can exist in its own bubble with little perceived application of cutting edge research. This can negatively impact the effectiveness with which important advice is received and acted upon by forecast users. AMMA-2050 incorporates climate scientists, sociologists, crop modellers, hydrological modellers and knowledge exchange partners who integrate tradition climate science into meaningful and usable climate advice. Example: Understanding how large scale wave structures change the dynamics of rainfall over West Africa may not be useful to a farmer. However, the subsequent advice on what crops are optimal to plant in the future given the change in seasonality of rainfall would be of great interest to the farmer. By integrating climate and impact sciences, AMMA-2050 aims to provide valuable science whilst furthering academic understanding of climate dynamics. 

Some questions for the research at Leeds:

• Why do high impact weather events occur? The climate is a very intricate system, but through analysis we can better understand the causes leading to a high impact weather event occurring. For example, what caused the massive flooding over Ouagadougou in 2009?
• How will high impact weather events change in the future (e.g. will extreme rains or dry spells be more frequent)?
• How can we help people over West Africa use climate information to adapt to climate change?

Examples of current research

Local Onset Regions (Fitzpatrick et al. 2016)

• Over West Africa, rainfall primarily comes from meso-scale convective systems (storms larger than 25,000 km2). But from a local perspective, the timing of onset (i.e. optimal planting date) can vary greatly over distances of 100 – 200 km in any direction. This finding led to previous research focusing on a more longitudinally-consistent proxy for onset date for research into inter-annual onset variability.
• Research at the University of Leeds, utilising a new and novel analytical method, has shown that large regions of West Africa have similar inter-annual variability in onset dates regardless of particular onset date (i.e. although the optimal planting date varies spatially and from year to year, the relative earliness or lateness of local planting dates is consistent over a much larger scale).
• This method has allowed for targeted analysis towards the specific causes of local onset variability; a problem previously thought unsolvable.
• The same analysis has been done over different monsoon regions, such as India.

Why is climate change important to me? Article in progress for the Bulletin of the American Meteorological Society

• There is often a language gap between science and policy across nations.
• In a similar way to how a maths student may ask “why do I need to learn fractions?” decision makers often ask “why do I need to know about climate change?” The answer to this is not straightforward and requires careful understanding of people’s perspectives.
• The paper is based on the successes of the jointly run BRACED and AMMA-2050 user workshop on climate resilience. At this workshop, policy makers from multiple backgrounds (mayors, government officials, town planners, members of the media etc.) came together to discuss the issue of climate change in Burkina Faso and how science can help improve public safety.
• This work also provides the first known academic collaboration between the main weather service provider in Burkina Faso (ANAM), and the largest meteorological research institute in the country (2IE).

Will heavy rains be more frequent in the future?

• Recent research suggests that the year-to-year trend of seasonal rainfall totals over West Africa (particularly 15°W–15°E, 11–18°N) is decoupled from the year-to-year trend in frequency of very intense storms.
  • In practice, this means that although West Africa is receiving the same amount of rainfall today that it was in the 1960’s, the way this rainfall is distributed through the season is very different.
• This change in seasonal distribution of rainfall can have serious consequences for inhabitants across West Africa. For example:
  • If rain events become less frequent in the future, will current crop selections be more likely to fail?
  • If intense rain events are more frequent in the future, will current flood defences be sufficient to prevent unnecessary loss of life/infrastructure?
• The University of Leeds is using a high resolution climate model to ascertain the causes behind the observed increase in intense rain event occurrences in the current climate. Using these findings, we hope to give meaningful advice on the potential for future change in intense rain event frequencies to help planning in the region.
• Although this work is in its preliminary stages, there is some evidence that the environment prior to large scale storms of different intensities varies substantially.

User relevant metrics atlas for future climate change 

• One of the key goals of AMMA-2050 is to provide decision first science.
• In practice, decision first science means providing impact modellers (crop models, flood models, sociologists) with relevant indicators of the state of the current and future climate.
• The University of Leeds, hosted scientists from across the UK and West Africa (including Ghana, Ivory Coast and Senegal) for a week long Python training course in December 2016.
• Under the guidance of the University of Leeds, African scientists are in the process of producing a user-relevant state of the environment atlas to give impact scientists the ability to quickly understand the predicted change in important climate metrics in the future. Examples of climate metrics calculated include: 

• Onset dates
• Seasonal maximum in consecutive dry days (i.e. longest seasonal dry spell)
• Frequency of intense rain events in a given month/season
• Frequency of very hot days

As part of this project, Dr Fitzpatrick has also created a publically available, climate metric general user interface. This interface is in development, but will eventually allow anyone to produce climate metric maps across Africa for their data. The developmental interface is available on GitHub, with a planned final version due by November 2017.

Collaborations with other institutions 

• ANACIM (Senegal) – Collaborative study on the 2014 drought over Senegal. This work involves the partnership of two early career researchers (one at each institution), who aim to understand the value of onset date selection for farmers and potential causes for the very dry 2014 season over Senegal. This work is expected to be submitted for peer review by the end of 2017.
• Jackson School of Geosciences, University of Texas in Austin – Dr Fitzpatrick will be hosted at the Jackson School of Geosciences by world leading West African scientists, Prof Kerry Cook and Dr Edward “Ned” Vizy. Their collaboration will clarify one of the main assumptions leading to uncertainty in the results in AMMA-2050. Namely: are high resolution climate models consistent in their interpretation of climate dynamics? The findings of this result will allow scientists on AMMA-2050 to robustly quantify the value of their findings.
• The Centre of Ecology and Hydrology in Wallingford, the UK Met Office, ANACIM, UCAD, and the University of Cape Coast – Production of the climate change metric atlas.
• Kings College London, the Centre of Ecology and Hydrology in Wallingford, the University of Sussex, ISRA, 2ie, ANAM and assorted members of the BRACED project – Article on the importance of integrating climate change with decision making strategies. Paper will be lead authored by the University of Leeds with involvement by people from a wide variety of backgrounds (both academic and institutional). The abstract has been accepted by the Bulletin of the American Meteorological Society with the full paper due for peer review before August 2017. 

Presentations

• Presentation on Local Onset Regions at the World Weather Open Science Conference – Montreal 2014