# Study of the Impact of Global Warming on the Productivity and Human Comfort of Workers of Farmers' Organizations in the Sahelian Zone of Cameroon

Alexis Dzokom, Darman Roger Djouldé

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Alexis Dzokom, Darman Roger Djouldé. Study of the Impact of Global Warming on the Productivity and Human Comfort of Workers of Farmers' Organizations in the Sahelian Zone of Cameroon. Mendeley Data, 2024, 2 (4), pp.1-15. [https://hal-04698848v1](https://hal.science/hal-04698848v1)

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# Study of the Impact of Global Warming on the Productivity and Human Comfort of Workers of Farmers' Organizations in the Sahelian Zone of Cameroon

Alexis Dzokom¹, Roger Djouldé Darman²

¹Department of Environmental Sciences, National Advanced School of Engineering, University of Maroua, Cameroon

²Department of Agriculture Animal Husbandry and By-Products, National Advanced School of Engineering, University of Maroua, Cameroon

## ABSTRACT

The objective of this work is to characterize the impact of heat wave situations on the productivity and human comfort of workers in peasant organizations in the Cameroonian Sahel zone. The Active Method of Participatory Research and Planning (MPRP) made it possible to collect socio-economic data through a series of 250 questionnaires. With Microsoft Office Excel, R and SPSS software, the descriptive analysis of the data consisted of calculating proportions (percentages, means and standard deviations), and creating graphs and tables. Overall, 3.85±0.83 women/hectare and 6.73±1.18 men/hectare work on a farm in the semi-arid Sahelian zone. In the dry season, a light work intensity of 156 watts induces a need for rest periods each hour in men starting at a WBGT of 30 °C, with a cumulative of 5±0.5 hours of rest during work times. While in women, a light work intensity of 156 watts induces a need for rest periods every hour at a WBGT of 30°C, with a cumulative 4.5±0.1 hours of rest during work times. During the dry season, the metabolic heat generated by physical activity in women in humid areas is 42.33±1.86°C and 42.32±1.17°C in semi-arid areas while in men in humid zones, it is 44.21±0.51°C and 45.69±1.66°C in semi-arid zones. These impacts of heat wave situations on the productivity and human comfort of workers in farmer organizations will provide a tool for managing heat wave risks in the Cameroonian Sahel environment.

Keywords: Sahelian zone, Heat waves, Impacts, Climate Change, Farmers' Organizations.

## INTRODUCTION

Cities will be exposed to climate change due to greenhouse gas-induced radiative forcing and localized effects of urbanization such as urban heat islands (Mark et al., 2010). Urban microclimates have long been recognized (Mark et al., 2010; Oke, 1987; Howard, 1833) in monitoring the detection of global climate change as being one of the consequences of urbanization most influencing the recording the history of climate change (Parker, 2010). This includes classic heat stress in addition to heat-induced episodes of pre-existing illnesses (i.e. respiratory, cardiovascular, nervous system disorders, etc.) (Mastrangelo et al., 2006; Ishigami et al., 2008; O'Neill and Ebi, 2009), generally in the very old, very young and those with a history of poor health (Falk, 1998; Davis et al., 2003; Donaldson et al., 2003). The global average temperature is increasing and is estimated to increase by a further 1.8 to 4.08°C (estimated average 3.08°C) by 2100, depending on measures taken to limit gas emissions to greenhouse effect (IPCC, 2008). It was then that climate change became a major concern of the international scientific community and countries around the world because of its potential and proven negative impacts on humans and ecosystems (Maurice et al., 2015). Regular observation of the frequency of extreme climatic events, false starts of rainy seasons, recent floods, recurrent droughts making the Sahel more and more victims, prove that climate change has ceased to be a strictly scientific question. Concerning the distant future of the planet to become a real and serious problem for our society. Projections from the latest generation of climate models (Kattenberg et al., 1995) suggest that global surface air temperatures will increase significantly in the future due to the radiative effects of increasing atmospheric gas concentrations at greenhouse effect (Thomas et al., 2014.). The urban population will be estimated at 6 billion city dwellers by 2050 (Mark P. et al., 2010). Ranging from rural to urban settings, many studies have explored perceptions of potential changes in the climate system associated with global warming (Kattenberg et al., 1995; Warrick et al., 1995; Stone, 1995; Santer et al., 1995). As part of this study, we examine the impact of global warming on workers' work productivity and human comfort through surveys carried out among workers in Sahelian environments. In other words, the objective of this article is to determine the periods favorable to productivity in a socio-professional environment in relation to changes in the measured heat index and the heat felt by workers in the Sahelian environment. This objective will make it possible to predict the behavior of humans in a socio-professional environment in the Sahel...

## 1- MATERIALS AND METHOD

### 1-1 Study sites

The study sites were identified in the regions of the Far North and North Cameroon, Sahelian zone, in ten localities, among members of associative movements and common initiative groups (GIC). These are the localities of Mokolo, Maroua, Mora, Garoua and Guider (for the Sahelian semi-arid zone according to the Ramsar Convention, 2006) and Waza, Makari, Lagdo, Yagoua and Maga (for the Sahelian humid zone according to the Ramsar Convention, 2006). These localities were chosen due to the fact that they are part of humid zones and semi-arid zones:
<figure><img src="image_2.png" /><figcaption>Figure 1: Coordinates of the chosen localities</figcaption></figure>

Three localities in the Northern region were chosen for the study while the other seven localities belong to the Far North region.

**1-1 Data collection method**

The Active Method of Research and Participation Planning (MARPP) used as part of this work consisted of more or less structured interviews (Dzokom, 2021). This socio-economic data collection tool aims to obtain information in person, individually or in small groups, through a series of questions asked. The information collected is recorded in a sheet serving as a conversation guide with the possibility of readjusting the questions during the interview. This method of data collection was carried out mainly during intense activities during daytime and nighttime heatwave periods in production sites: secretariats, households, schools, university establishments, training centers, libraries, shops, hospitals, administrations, agricultural sites, livestock areas, fishing sites, motorcycle taxis (etc.) in order to determine the impact of the heat felt on professional productivity and their economic performance specifically during these periods.

In total, 250 workers were surveyed in the ten study locations, i.e. 25 workers per location and 05±02 workers per sector of activity/per location. The workers surveyed were chosen randomly from the directory of workers available from formal state and union services. The survey took place from 2021 to 2023. The amount of information to be reported depends on the type of survey tools used and the stages of the survey. Overall, the questionnaire used included 9 sections:

* Identification of the worker: name, gender, age, level of education and experience in the professional environment;

* The worker's targets;

* Description of the activity carried out: targets, production levels, optimal production periods, means of production;

* The means of combating heat peaks: availability, capacity, type of energy used, cost, surface area covered by the activity, the method of combating high heat during work;

* The source of labor;

* Activities related to the profession carried out and warmth felt during these moments;

* The professional productivity system adopted during heat peaks;

* The perception of climatic disturbances;

* The experienced and/or perceived impacts of climate disruption;

* Adaptation strategies to climate disruptions.

**1-1 Data analysis**

The raw data are collected from each questionnaire, entered and formatted with Microsoft Office Excel software and imported in the form of text files (separator: tabulation) into R and SPSS software for subsequent statistical analyses, namely: analysis descriptive and the correlation test. The descriptive analysis consisted of calculations of proportions (percentages), means and standard deviations. Graphs and tables were constructed. The sperman correlation test made it possible to create a typology of the farms surveyed on the basis of the types of disturbance perceived. Given that the study sample was made up equally of men and women, only the variables “age” and “level of education” linked to workers were retained for this typology:
- The “age” variable has three modalities: the “Young” (JEUN) modality for workers whose age is < 45 years old, the “Aged” (AG) modality for workers whose age is between 45 years old and 60 years and the “Very elderly” (TAG) modality for workers whose age is > 60 years;

- The “level of education” variable has three categories: “workers without a formal level of education” (ANALF), workers who have reached the primary level of formal education (PRIM) and workers who have reached the secondary level (SEC) and more.

## 1-2 1-2 Assessment of heat stress in the workplace

To protect workers from the effects of heat exposure, “heat stress indices” and protection guidelines have been developed (Ramsey and Bernard, 2000). The most commonly used index in occupational health is the Wet Bulb Globe Temperature (WBGT) index developed by the US Army several decades ago (USDAAF, 2003). This index takes into account air temperature, radiant temperature, humidity and air movement, and forms the basis for working time limitations according to different heat exposure standards (stress index thermal, sweat rate predicted over four hours) (Tord et al., 2009; Kerslake, 1972) and are likely to be correlated with the WBGT which is only a combination of three local climate measurements (NIOSH, 1986):

* The natural temperature of the wet bulb, $T_{nwb}$;

* the global temperature, $T_g$; And

* air temperature, $T_a$.

When $WBGT_{-outside} = 0,7 \times T_{nwb} \times 0,2 \times T_g \times 0,1 \times T_a$; $WBGT_{-interior} = 0,7 \times T_{nwb} \times 0,3 \times T_g$.

The felt temperature (TR) is the link between the ambient temperature ($T_a$) and the wind speed (V). The temperature felt is expressed as follows:

$$TR = 13,12 + 0,6215Ta + (0,3965Ta - 11,37)V^{0,16}$$

## 1-3 1-3 Physiological and clinical impacts of heat stress

The human body is designed to maintain a core body temperature of 37°C (Tord et al., 2009). A person engaging in physical activity (e.g. while working) creates metabolic heat inside the body, which must be transferred to the person's external environment in order to avoid a dangerous increase in core body temperature (Parsons, 2003). The measurement of the physiological and clinical impact due to heat stress on workers will be done through the evaluation of the heat balance determined by the “six fundamental factors” following the Parsons method (2003), namely:

- (1) air temperature;

- (2) radiant temperature;

- (3) humidity;

- (4) air movement (wind speed);

- (5) clothing;

- (6) metabolic heat generated by human physical activity.

## 1-4 Impacts of heat exposure in the workplace

The physiological basis of the different levels of clinical damage to health has been briefly described above and more details are given by Parsons (2003) and Bridger (2003). Beyond acute heat stress, more chronic effects on the heart and kidneys can develop after excessive body heating or repeated dehydration (Bridger, 2003). Heat-related deaths at work have occasionally been reported when the “tolerance time” of working at different intensities until the core body temperature reaches 39°C (Tord et al., 2009). The factors studied here to determine the impact of heat exposure in the workplace are as follows:

- chronic effects on the heart and kidneys of heat in the workplace;

- effects of excessive body heating or repeated dehydration;

- heat-related deaths.

## 1-5 Impacts of heat exposure on worker productivity in the workplace

Protective clothing increases heat stress and reduces performance (Bernard, 1999). Heat stress is likely common during hot seasons, but culturally accepted methods to reduce impacts on health and work capacity (such as “napping”) are generally effective in avoiding serious health impacts. However, these culturally accepted methods will undoubtedly reduce the hourly productivity of exposed workers. The factors studied here to determine the impact of heat exposure on worker productivity in the workplace are:

- Number of nap hours during hot weather during work times;

- Productivity for workers in indoor climates in relation to times of air conditioning needs;

- The time to slow down work as a defense mechanism during strong exposure to heat;

- The effect of heat on work performance;

- The appearance of illnesses due to the effect of heat on workers.
## 1-6 1-6 Trends in climate change and heat stress in Sahelian cities

Ongoing global climate change has so far been described primarily in terms of average global temperature and temperature change. To describe changes in the workplace, heat stress requires analysis of trends in local temperature, humidity, wind speed and solar radiation (Tord et al., 2009). We will show temperature trends for selected locations as indicators of likely trends in actual local heat stress, but more detailed analysis is needed for projections of future impacts of local heat stress in the Sahel.

## 2-) - RESULT AND DISCUSSION

### 2-1) - Characteristics linked to the workers, operators and farms surveyed

The distribution of workers in the GICs and associations of the study sample by gender shows that these members surveyed are made up of 50% men (M) and 50% women (F) in the humid and semi-arid zone of the Cameroonian Sahel. In the humid zone, the average age of these workers is 32.63±1.29 years, while in the semi-arid zone the age of the surveyed workers is 31.95±1.25 years (Table 1).

In the humid zone, the majority of male members of the peasant organizations in the sample studied have a level of pre-school education, i.e. 83.94±12.21%, while in the semi-arid zone, the we observe 87.23±11.11% of workers having a pre-school level of education. Furthermore, in the humid zone, the majority of female members of peasant agricultural organizations in the sample studied have a level of pre-school education of 97.93±0.82%, while in the semi-arid zone, we observe 97.21±0.16% of women in peasant organizations with a pre-school level of education (Table 1).

We note in the wet zone that the male workers of GIC and associations achieve 4.57±0.39 tons/hectare of estimated production gains per rainy season and 1.94±0.06 tons/hectare of estimated production gains per dry season, while those in semi-arid zones have 4.24±0.10 tons/hectare of estimated production gains per rainy season and 1.92±0.04 tons/hectare of estimated production gains per dry season. We observe on average 3.85±0.83 women per farm who are sources of mainly salaried labor and often represent 95.45±3.43% in the semi-arid zone, while in the wetland, we observe on average 3.66±1.83 women per farm who are sources of mainly salaried labor and often represent 91.40±7.42% (Table 1).

The plant species most produced within GICs and associative and community movements, both in the dry season and in the rainy season in the two agro-ecological zones of the Sahelian environment are: Sorghum (99.62%); Onion (93.07%); Corn (84.78%); Peanut (60.84%); Cowpea (56.21%); Carrot (53.25%); Tomato (51.21%); potatoes (46.26%) and cabbages (45.83%) with a diversification index of 0.91 ± 0.09 per year, produced on average on 0.76 ± 0.48 hectares in the dry season, mainly near lowlands, rivers and lakes and on 0.67±0.74 hectares in the rainy season (Table 1).

In humid areas, the average output of men's work within associative movements is 966.28±221.22 kilograms/hectare in the dry season while in the rainy season, on average 846.94±163.73 kilograms/hectare is exploited by these men from the associative movements. In semi-arid areas, the average work output of associative movements is on average 962.54 ± 193.18 kilograms/hectare in the dry season, mainly near lowlands, rivers and lakes while. In the rainy season, on average 803.80 ± 133.58 kilograms/hectare is exploited by these associative movements. Furthermore, in humid areas, the average return on work of women in associative movements is 390.99±112.00 kilograms/hectare in the dry season and on average 508.12±248.33 kilograms/hectare in the rainy season while in semi-arid zones, the average labor output of women in associative movements is 230.20±60.27 kilograms/hectare in the dry season and on average 375.54±133.20 kilograms/hectare in the rainy season (Table 1).
<table><caption>Table 1: Characteristics of workers in the GICs and associations surveyed: gender, average age, level of education and number of years of professional experience</caption><caption>Characteristics of workers in the GICs and associations surveyed: gender, average age, level of education and number of years of professional experience</caption><thead><tr><th rowspan="2">Sites</th><th rowspan="2"></th><th colspan="2">Sex (%)</th><th colspan="2">Middle Age (ans)</th><th colspan="2">N.I.Prés (%)</th><th colspan="2">N.I.P. (%)</th><th colspan="2">N.I.Sec (%)</th><th colspan="2">Number of years of professional experience (years)</th></tr><tr><th>M</th><th>W</th><th>M</th><th>W</th><th>M</th><th>W</th><th>M</th><th>W</th><th>M</th><th>W</th><th>M</th><th>W</th></tr></thead><tbody><tr><td colspan="14" style="text-align: left; font-weight: bold;">Estimated production gains per season (Tons/hectare)</td></tr><tr><td rowspan="2">Wet area</td><td>Dry season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>1.94±0.06 T/ha</td><td>1.92±0.04 T/ha</td><td>2.25±0.97<br>T/ha</td><td>2.91±0.74<br>T/ha</td><td>2.65±0.44<br>T/ha</td><td>2.95±0.54<br>T/ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>4.57±0.39 T/ha</td><td>4.24±0.10 T/ha</td><td>7.45±0.97<br>T/ha</td><td>5.65±1.76<br>T/ha</td><td>7.78±0.33T/<br>ha</td><td>5.87±0.65<br>T/ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td rowspan="2">Semi-arid zone</td><td>Dry season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>1.79±0.28 T/ha</td><td>1.36±0.36 T/ha</td><td>9.17±2.86<br>T/ha</td><td>6.44±1.88<br>T/ha</td><td>9.54±2.56T/<br>ha</td><td>6.76±1.33<br>T/ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>2.80±1.12 T/ha</td><td>1.12±0.37 T/ha</td><td>8.32±1.54<br>T/ha</td><td>7.89±1.31<br>T/ha</td><td>8.86±1.87<br>T/ha</td><td>7.94±0.19<br>T/ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td colspan="14" style="text-align: left; font-weight: bold;">Characteristics (Proportions of people) linked to the farms used and surveyed (%)</td></tr><tr><td>Wet area</td><td></td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>09.06±0.82</td><td>91.40±7.42</td><td>60.09±05.77</td><td>39.41±0.93</td><td>96.34±04.55</td><td>03.65±3.53</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td>Semi-arid zone</td><td></td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>05.49±0.61</td><td>95.45±3.43</td><td>50.98±02.61</td><td>49.54±8.67</td><td>95.08±01.26</td><td>04.59±6.87</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td colspan="14" style="text-align: left; font-weight: bold;">Main plant species produced</td></tr><tr><td>Wet area</td><td></td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>Sorghum (99.62%); Onion (93.07%); Corn (84.78%); Peanut (60.84%); Cowpea (56.21%); Carrot (53.25%); Tomato (51.21%); Potato (46.26%) and Cabbage (45.83%).</td><td></td><td></td><td></td><td></td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td>Semi-arid zone</td><td></td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>Sorghum (99.62%); Onion (93.07%); Corn (84.78%); Peanut (60.84%); Cowpea (56.21%); Carrot (53.25%); Tomato (51.21%); Potato (46.26%) and Cabbage (45.83%).</td><td></td><td></td><td></td><td></td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td colspan="14" style="text-align: left; font-weight: bold;">Area covered by the activity (hectare/day)</td></tr><tr><td rowspan="2">Wet area</td><td>Dry season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>0.76±0.48 ha</td><td>0.67±0.74 ha</td><td>0.86±0.55 ha</td><td>0.82±0.63ha</td><td>0.98±0.07 ha</td><td>0.89±0.83ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>2.35±0.92 ha</td><td>1.58±0.62 ha</td><td>2.78±0.29ha</td><td>1.93±0.85ha</td><td>2.93±0.78 ha</td><td>1.99±0.09ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td rowspan="2">Semi-arid zone</td><td>Dry season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>0.83±0.02 ha</td><td>0.23±0.65 ha</td><td>0.92±0.84 ha</td><td>0.34±0.33<br>ha</td><td>0.98±0.32 ha</td><td>0.47±0.09<br>ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>1.34±0.34 ha</td><td>0.94±0.62 ha</td><td>1.97±0.22ha</td><td>0.97±0.75<br>ha</td><td>1.98±0.29ha</td><td>0.99±0.83<br>ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td colspan="14" style="text-align: left; font-weight: bold;">Producers' labor yield (kilogram/hectare)</td></tr><tr><td rowspan="2">Wet area</td><td>Dry season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>846.94±63.73<br>Kg/ha</td><td>390.99±11.00<br>Kg/ha</td><td>868.39±22.03<br>Kg/ha</td><td>393.23±02.<br>51 Kg/ha</td><td>894.05±09.0<br>6 Kg/ha</td><td>402.64±09.<br>93 Kg/ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>32.63±1.29</td><td>30.28±1.04</td><td>966.28±21.22<br>kg/ha</td><td>508.12±48.33<br>Kg/ha</td><td>974.03±02.23<br>g/ha</td><td>574.12±35.<br>64 Kg/ha</td><td>989.74±08.9<br>2 g/ha</td><td>593.73±08.<br>05 Kg/ha</td><td>9.77±0.23</td><td>09.57±0.44</td></tr><tr><td rowspan="2">Semi-arid zone</td><td>Dry season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>962.54±13.18<br>Kg/ha</td><td>230.20±60.27<br>Kg/ha</td><td>968.59±96.81<br>Kg/ha</td><td>239.08±93.<br>66 Kg/ha</td><td>979.52±06.3<br>3 Kg/ha</td><td>289.55±04.<br>92 Kg/ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr><tr><td>Rainy season</td><td>50%</td><td>50%</td><td>31.95±1.25</td><td>29.98±0.93</td><td>803.80±33.58<br>Kg/ha</td><td>375.54±13.20<br>Kg/ha</td><td>844.23±03.02<br>Kg/ha</td><td>394.92±04.<br>20 Kg/ha</td><td>892.97±08.9<br>7 Kg/ha</td><td>407.89±02.<br>85Kg/ha</td><td>9.59±0.69</td><td>09.78±0.68</td></tr></tbody></table>

With M=men and F=women
In semi-arid zones, the surface area of land covered by activity is higher than in humid zones. This would be due to the problem of access to fertile land because, during our study we noted that the land rented to them is mostly unproductive compared to that exploited by men.

**2-2-)- Assessment of heat stress in the workplace within GICs and associations**

During the dry season, at a light work intensity of 156 watts, the need for rest periods per hour for men begins at a WBGT of 30°C, with a cumulative 5±0.5 hours of rest during periods work, while at an intense work intensity of 200 W during the rainy season, this threshold occurs at a WBGT of approximately 30°C with a cumulative 5±1.5 hours of rest during work times. The need for preventive actions to avoid excessive heat exposure in men begins even earlier, during rest: during the dry season, at an approximate metabolic rate of 96 watts, the need for rest periods every hour in men begins at a WBGT of 33°C, with a cumulative rest of 5±1.5 hours, while at an approximate metabolic rate of 100 W during the rainy season this threshold occurs at a WBGT of approximately 33 °C with a cumulative rest of 5±2 hours.

During the dry season, for women, at a light work intensity of 156 watts, the need for rest periods each hour begins at a WBGT of 30°C, with a cumulative of 4.5±0.1 hours of rest during work times, while at an intense work intensity of 200 W during the rainy season, this threshold occurs at a WBGT of approximately 30°C with an accumulation of 3±1.5 hours of rest during time of work. The need for preventive actions in women, to avoid excessive exposure to heat, begins even earlier, during rest: during the dry season, at an approximate metabolic rate of 96 watts, the need for rest periods every hour begins at a WBGT of 33°C, with a cumulative rest of 4±0.1 hours, while at an approximate metabolic rate of 100 W during the rainy season, this threshold occurs at a WBGT of approximately 33°C with a cumulative 3±0.2 hours of rest.

<figure><img src="image_3.png" /></figure>

With M=men and F=women

<caption>**Graph 1:** Light workplace heat stress during dry and rainy seasons</caption>

During the dry season, for men, at an average work intensity of 262 watts, the need for rest periods each hour begins at a WBGT of 28°C, with a cumulative 6±1.5 hours of rest during the dry season. work time, while at an average work intensity of 300 W during the rainy season, this threshold occurs at a WBGT of approximately 28°C with a cumulative 5±1.5 hours of rest during work times. During the dry season, for men, at an intense work intensity of 374 watts, the need for rest periods each hour begins at a WBGT of 25°C, with a cumulative 8±1.5 hours of rest during the dry season. work time, while at an average work intensity of 400 W during the rainy season, this threshold occurs at a WBGT of around 25°C with a cumulative 5±0.5 hours of rest during work times (Graph 2). The need for preventive actions to avoid excessive exposure to heat begins even earlier in men, during very intense work.

<figure><img src="image_4.png" /></figure>

With M=men and F=women

<caption>**Graph 2:** Thermal stress at the work site medium, intense and very intense during the dry and rainy seasons</caption>

During the dry season, at an approximate metabolic rate of 437 watts, the need for rest periods each hour begins at a WBGT of 23°C, with a cumulative rest of 7±1.5 hours, while at a rate approximate metabolic rate of 500
W during the rainy season, this threshold occurs at a WBGT of approximately 23°C with a cumulative $5\pm1.5$ hours of rest (Table 10). Very intense work is often reserved for men.

During the dry season, for women at an average work intensity of 289 watts, the need for rest periods each hour begins at a WBGT of 28°C, with a cumulative $4.5\pm0.5$ hours of rest during work times, while at an average work intensity of 329 W during the rainy season, this threshold occurs at a WBGT of approximately 28°C with an accumulation of $3.5\pm0.5$ hours of rest during work times. During the dry season, for women at an intense work intensity of 394 watts, the need for rest periods each hour begins at a WBGT of 25°C, with a cumulative $6.5\pm0.5$ hours of rest during work times, while at an average work intensity of 428 W during the rainy season, this threshold occurs at a WBGT of approximately 25°C with an accumulation of $3.5\pm0.5$ hours of rest during work times (Graph 2).

### 2-3-) - Metabolic heat generated by human physical activity

The number of hours of rest in the shade between [10-16] (Hours) in women is higher than in men and is a function of age in both sexes. The age group between [26-40] years rests on average for 2 hours for women and 1.5 hours for men while the age group between [41-100] years rests on average for 4 hours 30 minutes for women and 3 hours 30 minutes for men, per day on sunny days.

<figure><img src="image_5.png" /><figcaption>**Graph 3:** Protection against sunstroke and number of hours of rest in the shade between 10 a.m.-4 p.m.</figcaption></figure>

The level of protection against sunstroke is more marked in the age group [61-100] years for both women and men. The number of baths and cold hydration are higher in the young age group between [26-30] years both in women and in men while in the same age group we observe a high consumption of hot drink while it is low in women during sunny days.

<figure><img src="image_6.png" /><figcaption>**Graph 4:** Level of protection against sunstroke via hydration and water supply</figcaption></figure>

The rates of use of non-renewable energy ventilation systems and exposure to open air are higher in all young age groups, both women and men. Artificial ventilation is used much more by the age groups of [26-30] years and that of [31-40] years while natural ventilation is used much more in the same age group both among women and at men's. Exposure to the open air is preferred for all units except in the event of the presence of particles and dust in the air.
<figure><img src="image_7.png" /><figcaption>**Graph 5:** Level of protection against insolation via ventilation systems.</figcaption></figure>

Overall, a low level of protection against sunstroke is observed in the age group of [0-30]years during sunny days while in the age groups of [31-100]years, the level of protection against sunstroke via the use of ventilation systems is higher

<figure><img src="image_8.png" /></figure>

With M=men and F=women

<caption>**Graph 6:** Level of protection against sunstroke via clothing protection systems</caption>

The rate of use of towels and other cloths to wipe away heat changes with age and is more pronounced among women than among men. However, the average number of items of clothing used to protect themselves from the sun by women is 02 items of clothing per day. The level of protection against sunstroke varies according to the age of the respondents.

<figure><img src="image_9.png" /></figure>

With M=men and F=women

<caption>**Graph 7:** Level of protection against sunstroke depending on the average metabolic temperature generated by human physical activity (°C)</caption>

The level of protection against sunstroke depends on the average metabolic temperature generated by physical activity. In humid areas as in semi-arid zones, the level of protection against sunstroke is averagely higher in the dry season (1, 1 in humid zone and 1.2 in semi-arid zone) than in the rainy season (0.6 in humid zone and 0.7 in semi-arid zone) while the average metabolic temperatures generated by the physical activity of women is averagely higher in the dry season (42.33°±1.43°C in humid zone and 29.95±1.99°C in semi-arid zone) than in men (44.95±4.29 °C in humid areas and
28.14°±1.05°C in semi-arid areas). In the rainy season, the average metabolic temperatures generated by the physical activity of women are averagely lower (30.00±0.29°C in humid zones and 29.91±1.04°C in semi-arid zones).

<figure><img src="image_10.png" /></figure>

With M=men and F=women

<caption>**Graph 8:** Activity level according to the average metabolic temperature generated by human physical activity (°C)</caption>

The activity level is a function of the average metabolic temperature generated by physical activity: In humid areas, the activity level is averagely lower in the dry season (1.78±0.07 in women and 1.40±0.03 in men) than in the rainy season (3.91±0.04 in women and 3.25±0.04 in men). In semi-arid zones, the activity level is averagely lower in the dry season (1.98±0.01 in women and 1.04±0.08 in men) than in the rainy season (4.01±0.03 in women and 3.40±0.05 in men). In humid areas, the average metabolic temperatures generated by physical activity are also averagely higher in the dry season (42.34±01.06 °C in women and 42.32±01.04 °C in men) less high in the rainy season (27.86±00.67°C in women and 30.00±01.31°C in men). In semi-arid zones, the average metabolic temperatures generated by physical activity are also averagely higher in the dry season (42.33±01.74 °C in women and 45.69±01.65 °C in men) lower in the rainy season (29.91±01.75°C for women and 28.48±01.15°C for men).

In humid areas, the activity level is averagely lower in the dry season (1.78±0.07 in women and 1.40±0.03 in men) than in the rainy season (3.91±0.04 in women and 3.25±0.04 in men). In semi-arid zones, the activity level is averagely lower in the dry season (1.98±0.01 in women and 1.04±0.08 in men) than in the rainy season (4.01±0.03 in women and 3.40±0.05 in men).

<figure><img src="image_11.png" /></figure>

With M=men and F=women

<caption>**Graph 9:** Activity level according to the level of protection against sunstroke</caption>

In humid areas, the level of protection against sunstroke is averagely higher in the dry season (1.1 for men and 1.9 for women) than in the rainy season (0.6 for men and 1.64 among women). In semi-arid zones, the level of protection against sunstroke is averagely higher in the dry season (1.2 in men and 1.5 in women) than in the rainy season (0.7 in men and 1.85 in women).

## 2-4) Physiological and clinical impacts of heat stress

The results collected in the dry season show that the average air temperature is 41.56±1.17 °C in the humid zone and 41.45±1.63 °C in the semi-arid zone with a radiant temperature of 42.68±0.97°C in humid areas and 42.56±1.52°C in semi-arid areas. The metabolic heat generated by the physical activity of women in the humid zone is 42.33±1.86 °C and 42.32±1.17 °C in the semi-arid zone while the metabolic heat generated by the activity The physical temperature
of men in humid zones is 44.21±0.51°C and 45.69±1.66°C in semi-arid zones. The average air humidity is 07.422±0.92% in the humid zone and 01.83±0.31% in the semi-arid zone and the average wind speed is 14.02±1.03 Km/s in humid areas and 16.8±1.41 Km/s in semi-arid areas.

<figure><img src="image_12.png" /><figcaption>**Graph 10:** Evaluation of the heat balance due to work in the dry season</figcaption></figure>

In the rainy season, the average air temperature is 41.56±1.17°C in the humid zone and 41.45±1.63°C in the semi-arid zone with a radiant temperature of 42.68±0.97°C in humid areas and 42.56±1.52°C in semi-arid areas. The metabolic heat generated by the physical activity of women in the humid zone is 42.33±1.86 °C and 42.32±1.17 °C in the semi-arid zone while the metabolic heat generated by the activity The physical temperature of men in humid zones is 44.21±0.51°C and 45.69±1.66°C in semi-arid zones. The average air humidity is 07.422±0.92% in the humid zone and 01.83±0.31% in the semi-arid zone and the average wind speed is 14.02±1.03 Km/s in humid areas and 16.8±1.41 Km/s in semi-arid areas.

<figure><img src="image_13.png" /><figcaption>**Graph 11:** Evaluation of the heat balance due to work in the dry season</figcaption></figure>

If cooling by transpiration and convection (by contact with cooler air and by air movement) is not sufficient, metabolic heat generation must be reduced to avoid thermal stress and heat stroke. (Tord et al., 2009; Ramsey and Bernard; 2000) which could be limitations to the extent that physical activity and work performance can be maintained without rest periods. When physical activity is high in a hot working environment, the worker risks an increase in body temperature (above 38°C), a decrease in physical work capacity (Kerslake, 1972, Bridger; 2003), decreased mental work capacity (Ramsey, 1995) and increased accident risk (Ramsey et al., 1983), and possibly heat exhaustion or heat stroke (Hales and Richards, 1987).

The main factor causing these effects is increased core body temperature (Leithead, 1964), but dehydration due to sweating and insufficient fluid intake is also of major importance (Schrier et al., 1970). Symptomatic exhaustion and clinical illness, particularly kidney disease (Schrier et al., 1970), can be the result of excessive dehydration (Bridger; 2003). When body temperature exceeds 39°C, acute heat disorders (heat stroke) can occur, and above 40.68°C, potentially fatal “severe hyperpyrexia” begins to occur (Leithead, 1964). The first report on this issue in the context of global climate change (Kjellstrom, 2000) compared the effect of heat on work performance to "disability" caused by defined illnesses, and concluded that this effect could contribute to disability in a population to a greater extent than most diseases.

## 2-5) - Impacts of heat exposure in the workplace
In the dry season, at a WBGT of 32°C, the tolerance time during light work drops below one hour and it decreases by 12 minutes per 8°C increase in WBGT during rest (100% rest/ hour) where we observe 39°C while in the rainy season, at a WBGT of 31°C, the tolerance time during light work goes above 3/4 of an hour and decreases by 15 minutes by 10°C increase in WBGT during rest (100% rest/hour) where 39°C is observed.

For average work, in the dry season, at a WBGT of 30°C, the tolerance time drops below one hour during intense work (50% rest/hour) and it decreases by 10 minutes per increase of 9 °C of the WBGT during rest (100% rest/hour) where we observe 38°C while in the rainy season, at a WBGT of 28°C, the tolerance time in average work goes above 3/4 of an hour and it decreases by 10 minutes per 11°C increase in WBGT during rest (100% rest/hour) where we observe 39°C.

<figure><img src="image_14.png" /><figcaption>**Graph 12:** Work intensity during light and medium work</figcaption></figure>

In the dry season, at a WBGT of 29°C, the tolerance time during heavy work drops below one hour and it decreases by 10 minutes per 11°C increase in WBGT during rest (100% rest/ hour) where we observe 39°C while in the rainy season, at a WBGT of 27°C, the tolerance time during heavy work goes above 3/4 of an hour and decreases by 15 minutes by 10°C increase in WBGT during rest (100% rest/hour) where 36°C is observed.

During average work, in the dry season, at a WBGT of 27°C, the tolerance time drops below one hour during very heavy work (50% rest/hour) and it decreases by 10 minutes per increase in 10°C of the WBGT during rest (100% rest/hour) where we observe 36°C while in the rainy season, at a WBGT of 25.5°C, the tolerance time during average work passes above 3/4 hour and it decreases by 10 minutes per 11°C increase in WBGT during rest (100% rest/hour) where 34°C is observed.

<figure><img src="image_15.png" /><figcaption>**Graph 13:** Work intensity during heavy and very heavy work</figcaption></figure>

In humid areas, the “calculated Wet Bulb Globe Temperature Index (WBGT)” is governed by the natural temperature of the average wet bulb (Tnwb) which is 37.74±0.15°C, the WBGT-(without solar radiation) Calculated average of 33.73±0.49°C, the WBGT-(with solar radiation) Calculated average of 35.58±0.19°C under an average air temperature (Ta) °C of 41, 57±1.17°C.

<figure><img src="image_16.png" /><figcaption>**Graph 14:** Wet Bulb Globe Temperature (WBGT) index calculated</figcaption></figure>
In semi-harsh areas, the "calculated Wet Bulb Globe Temperature Index (WBGT)" is governed by the natural temperature of the average wet bulb ($T_{nwb}$) which is 37.28±0.19°C, the WBGT-(without radiation solar) Calculated average of 33.59±0.13°C, the WBGT-(with solar radiation) Calculated average of 35.24±0.09°C under an average air temperature ($T_a$) °C of 41.45±1.63°C.

The relationship between exposure to heat in the workplace and productivity determined by Axelsson (1974), Holmer (1996) and Tord et al., (2009) made it possible to quantify this relationship in work situations where workers follow their own pace (Tord et al., 2009).

Slowing down work as a defense mechanism during high heat exposure is referred to as "autonomous adaptation" by Ebi et al. (2005) in their work on climate change.

Productivity has also been analyzed for indoor climates in relation to air conditioning requirements (Parsons, 2003). A number of recent studies have analyzed different aspects of the effects of heat exposure on productivity. In outdoor environments, increased exposure to heat reduces the performance of field workers and leads them to observe alternative rest times more or less equal to work time. Thus, reducing the air temperature in fields in humid areas improves the perception of the working environment better than in semi-arid areas.

Protective clothing increases heat stress and reduces performance in the dry season. Heat stress is likely common during hot seasons, but culturally accepted methods to reduce impacts on health and work capacity (such as "naps") are generally effective in avoiding serious health impacts (Bernard, 1999; Tord et al., 2009). However, these culturally accepted methods will undoubtedly reduce the hourly productivity of female workers exposed to health fields (Tord et al., 2009).

## 2-6) - Trends in climate change and heat stress in Sahelian cities

Maximum mean and minimum temperature trends for humid and semi-arid areas were compiled over 10 years (2013-2023).

In the dry season in the humid Sahel zone, the average maximum daytime temperature is +41.56± 1.16°C/season while the average maximum nighttime temperature is +31.31± 1.05°C/season. In the semi-arid zone, in the dry season, the average maximum daytime temperature is +41.45± 1.63°C/season while the average maximum nighttime temperature is +30.42± 3.15°C/season.

In the rainy season in the humid Sahel zone, the average maximum daytime temperature is +39.59± 0.69°C/season while the average maximum nighttime temperature is +22.16± 1.56°C/season. In the semi-arid zone, in the rainy season, the average maximum daytime temperature is +39.83± 1.32°C/season while the average maximum nighttime temperature is +25.47± 4.01°C/season.

<figure><img src="image_17.png" /><figcaption>**Graph 15:** Maximum temporal trends, fitted line and temperature increase for humid and semi-arid areas</figcaption></figure>

In the dry season in the humid Sahel zone, the average daytime temperature is +41.15± 1.07°C/season while the average nighttime temperature is +29.94± 1.16°C/season. In the semi-arid zone, in the dry season, the average daytime temperature is +40.76± 1.26°C/season while the average nighttime temperature is +29.72± 3.21°C/season.

In the rainy season in the humid Sahel zone, the average daytime temperature is +38.78± 0.62°C/season while the average nighttime temperature is +21.64± 1.37°C/season. In the semi-arid zone, in the rainy season, the average daytime temperature is +39.09± 1.34°C/season while the average nighttime temperature is +25.20± 3.94°C/season.

<figure><img src="image_18.png" /><figcaption>**Graph 16:** Mean temporal trends, fitted line, and temperature increase for humid and semi-arid areas</figcaption></figure>

In the dry season in the humid Sahel zone, the average daytime minimum temperature is 37.05± 1.07°C/dry season while the average nighttime minimum temperature is +25.66± 1.96°C/season dried. In the semi-arid zone, in the dry
season, the average minimum daytime temperature is +37.38±2.27°C/dry season while the average minimum nighttime temperature is +22.46±3.78°C/ dry season.

In the rainy season in the humid Sahel zone, the average daytime minimum temperature is +34.07± 1.10°C/ rainy season while the average nighttime minimum temperature is +21.64± 1.37°C/ rainy season. In the semi-arid zone, in the rainy season, the average minimum daytime temperature is +33.25±1.91°C/rainy season while the average minimum nighttime temperature is +20.25±3.83°C/ rainy season.

<figure><img src="image_19.png" /><figcaption>**Graph 17:** Temporal trends mean minimums, fitted line, and temperature increase for humid and semi-arid areas</figcaption></figure>

In many of these regions, maximum temperatures during the hottest part of the year are already close to 40°C (Tord et al., 2009) and increasing over time (Figure 17). An additional temperature of 3°58°C will make work (e.g. in agriculture and construction work) very difficult during the hottest periods in most of these cities and in tropical countries in general. Ongoing temperature changes are caused in part by the "heat island effect" in many of these cities.

## CONCLUSION

As part of this study, the objective is to examine the perceptions of women workers within women's peasant organizations from various economic, social and environmental sectors of activity and a direct measurement of the impact of global warming on their productivity to work and human comfort.

In sum, 3.85±0.83 women/hectare and 6.73±1.18 men/hectare work on a farm in the semi-arid Sahelian zone. 95.45±3.43% of women are a source of labor and 62.49±0.61% are a predominantly community source of labor. 01.72±1.13% of women are owners of the land made available for the agricultural activities of peasant organizations in the rainy season compared to 91.07±2.04% of the land is made available by male owners of GIC for agricultural activities in the rainy season.

During the dry season, at a light work intensity of 156 watts, the need for rest periods per hour for men begins at a WBGT of 30°C, with a cumulative 5±0.5 hours of rest during periods work while in women, at a light work intensity of 156 watts, the need for rest periods each hour begins at a WBGT of 30°C, with a cumulative 4.5±0.1 hours of rest during work times. The number of hours of rest in the shade between [10-16] (Hours) in women is higher than in men and is a function of age in both sexes. The results collected in the dry season show that the average air temperature is 41.56±1.17 °C in the humid zone and 41.45±1.63 °C in the semi-arid zone with a radiant temperature of 42.68±0.97°C in humid areas and 42.56±1.52°C in semi-arid areas. The metabolic heat generated by the physical activity of women in the humid zone is 42.33±1.86 °C and 42.32±1.17 °C in the semi-arid zone while the metabolic heat generated by the activity physical condition of men in humid zone is 44.21±0.51 °C in and 45.69±1.66 °C in semi-arid zone.

The level of protection against sunstroke depends on the average metabolic temperature generated by physical activity: In humid areas as in semi-arid zones, the level of protection against sunstroke is averagely higher in the dry season (1, 1 in humid zone and 1.2 in semi-arid zone) than in the rainy season (0.6 in humid zone and 0.7 in semi-arid zone) while the average metabolic temperatures generated by the physical activity of women is averagely higher in the dry season (42.33°±1.43°C in humid zone and 29.95±1.99°C in semi-arid zone) than in men (44.95±4.29 °C in humid areas and 28.14°±1.05°C in semi-arid areas). In the rainy season, the average metabolic temperatures generated by the physical activity of women are averagely lower (30.00±0.29°C in humid zones and 29.91±1.04°C in semi-arid zones).

The activity level is a function of the average metabolic temperature generated by physical activity: In humid areas, the activity level is averagely lower in the dry season (1.78±0.07 in women and 1.40 ±0.03 in men) than in the rainy season (3.91±0.04 in women and 3.25±0.04 in men). In semi-arid zones, the activity level is averagely lower in the dry season (1.98±0.01 in women and 1.04±0.08 in men) than in the rainy season (4. 01±0.03 in women and 3.40±0.05 in men).

In humid areas, the average metabolic temperatures generated by physical activity are also averagely higher in the dry season (42.34±01.06 °C in women and 42.32±01.04 °C in men) and lower in the rainy season (27.86±00.67°C for women and 30.00±01.31°C for men). In semi-arid zones, the average metabolic temperatures generated by physical activity are also averagely higher in the dry season (42.33±01.74 °C in women and 45.69±01.65 °C in men) lower in the rainy season (29.91±01.75°C for women and 28.48±01.15°C for men)
In the dry season, at a WBGT of 32°C, the tolerance time during light work drops below one hour and it decreases by 12 minutes per 8°C increase in WBGT during rest (100% rest/ hour) where we observe 39°C while in the rainy season, at a WBGT of 31°C, the tolerance time during light work goes above 3/4 of an hour and decreases by 15 minutes by 10°C increase in WBGT during rest (100% rest/hour) where 39°C is observed.

For average work, in the dry season, at a WBGT of 30°C, the tolerance time drops below one hour during intense work (50% rest/hour) and it decreases by 10 minutes per increase of 9 °C of the WBGT during rest (100% rest/hour) where we observe 38°C while in the rainy season, at a WBGT of 28°C, the tolerance time in average work goes above 3/4 of an hour and it decreases by 10 minutes per 11°C increase in WBGT during rest (100% rest/hour) where we observe 39°C.

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